IPTV Basics

All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying recording or by any information storage and retrieval system without written permission from the authors and publisher, except for the inclusion of brief quotations in a review. Copyright c 2006, 2007 By Althos Publishing First Printing Printed and Bound by Lightning Source, TN. Every effort has been made to make this manual as complete and as accurate as possible. However, there may be mistakes both typographical and in content. Therefore, this text should be used only as a general guide and not as the ultimate source of IP Television information. Furthermore, this manual contains information on telecommunications accurate only up to the printing date. The purpose of this manual to educate. The authors and Althos Publishing shall have neither liability nor responsibility to any person or entity with respect to any loss or damage caused, or alleged to be caused, directly or indirectly by the information contained in this book.

International Standard Book Number: 1-932813-56-X

About the Author

Mr. Harte is the president of Althos, an expert information provider which researches, trains, and publishes on technology and business industries. He has over 29 years of technology analysis, development, implementation, and business management experience. Mr. Harte has worked for leading companies including Ericsson/General Electric, Audiovox/Toshiba and Westinghouse and has consulted for hundreds of other companies. Mr. Harte continually researches, analyzes, and tests new communication technologies, applications, and services. He has authored over 80 books on telecommunications technologies and business systems covering topics such as mobile telephone systems, data communications, voice over data networks, broadband, prepaid services, billing systems, sales, and Internet marketing. Mr. Harte holds many degrees and certificates including an Executive MBA from Wake Forest University (1995) and a BSET from the University of the State of New York, (1990).

Chapter 1
Internet Protocol Television(IPTV)
IPTV is a process of sending television signals over IP data networks .Broadband access providers . These IP networks can be managed (e. Packet routing information is then added to the digital video and voice signals so they can be routed through the Internet or data network. To get IPTV you need these key parts: . If the television signal is in analog form (standard TV or HDTV) the video and audio signals are first converted to a digital form.Media content providers
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. Broadband access providers supply the high-speed data connection that can transfer the digital video television signals. broadband Internet).g. Media content providers create information that people want to view or obtain. Service providers identify and control the connections between the viewing devices and the content providers (media sources).g.IPTV service providers . The viewing devices or adapters convert digital television signals into a form that can be controlled and viewed by users. DSL or Optical) or they can be unmanaged (e.Viewing devices or adapters .

Figure 1.1. multimedia mobile telephones and IPTVs. Television adapters convert digital television signals into standard television RF connections that allow standard televisions to watch IPTV channels. Multimedia computers (desktops and laptops) allow some viewers to watch Internet television programs without the need for adapters provided they have the multimedia browsers that have the appropriate media plug-ins. This diagram shows that some of the options for viewing devices include multimedia computers. IP televisions are devices that are specifically designed to watch television channels through IP data networks without the need for adapter boxes or media gateways.1 shows several types of IPTV viewing devices. IPTV Viewing Devices
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. television adapter boxes. Television adapters (set top boxes) connect standard television RF or video and audio
Figure 1.IPTV Basics
The key types of IPTV viewing devices include multimedia computers. Multimedia computers have video processing and audio processing capabilities. television adapters. IP televisions and mobile telephones.

This diagram shows that some of the common types of broadband access systems that are available include powerline data distribution. WLAN. Mobile telephones that have multimedia play capabilities along with broadband wireless services and the necessary media gateways. MMDS.Chapter 1
connectors to data jacks or wireless LAN connections. Broadband access providers transfer high-speed data to the end users. cable modems.
Figure 1. digital subscriber lines (DSL) and wireless local area network systems (3G wireless. Figure 1.2.2 shows the key types of broadband access providers that can be used to provide Internet television service. IP televisions can be directly connected to data jacks or wireless LAN connections. and LMDS). The type of technology used by broadband access providers can play an important part in the ability and/or quality of IPTV services. Broadband Access Providers
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3. IPTV Service Providers
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Figure 1. While it is possible in some cases for end users to directly connect to a media source by using an IP address or even a web link. When television channel requests are processed.IPTV Basics
Internet television service providers (ITVSPs) help customers find Internet television channels and manage connections between media sources. The ITVSP then can use this billing information to charge the customer for channels viewed.3 shows that Internet television service providers (ITVSPs) are primarily made of computers that are connected to the Internet and software to operate call processing and other services. Figure 1. Internet television service providers may also provide connections to subscription controlled television sources. Internet television provides may simplify (and limit) the programming guide choices. These media gateways transfer their billing details to a clearinghouse so the ITVSP can pay for the gateway’s usage. the IPTV service provider makes a business relationship with the media source. the ITVSP sends messages to gateways via the Internet allowing television channels to be connected to a selected media gateway source (such as television channels). The IPTV service provider may pay the content provider a fixed fee or share the revenue from funds it collects from their end user. For this role. a computer keeps track of which customers are active (registration) and what features and services are authorized. In this diagram.

television programs.4 shows some of the existing and new types of IPTV content providers. Private video sources are provided by companies or people who are willing to provide and pay to have their signals available on television. news services and other information sources. upload their content (such as pictures and videos) and share their content with other IPTV viewers. IPTV systems can be provided through broadband communication systems that can reach content providers and viewers in any part of the world. Traditional television network content sources include movies. public video sources and private video sources. Television networks have traditionally been a closed distribution system where the television network determined which program sources could reach viewers. Figure 1. education. New types of content sources include personal media channels. education sources and sports channels. satellite systems and VHF/UHF transmission systems have a limited number of channels (up to several hundred channels). Television networks such as cable television. sports channels. Personal media channels allow viewers to create their own television channel. interactive media. video rentals. IPTVs may provide access to interactive media such as games.Chapter 1
Content providers create different types of television media programs that are distributed through a variety of media distribution channels. and television networks. popular public places and public web cams. chat rooms and e-commerce shopping. global television channels. This diagram shows that IPTV content includes traditional television content sources such as movies. Some of the more popular global television channels that are available on IPTV include news channels. This allows IPTV service providers to offer many new content programs that have not been available for standard television distribution systems. reli-
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. Some common private television channels include religious groups. news services. airlines and specialty channels. business channels and music television. pay per view. sports. IPTV systems provide access to television channels throughout the world. Common program distribution channels include movie theaters. Governments and public groups have begun providing real time video access to public sources such as courtrooms.

More services
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.4. More control 3.
Figure 1. global television channels. New types of IPTV content include personal media.IPTV Basics
gious and other forms of one-way information content. IPTV Media Content Providers
Why Consider IPTV and Internet Television Services
There are three key reasons why people and companies are adding to or converting their existing television systems to television over data network capabilities: 1. public video sources and private video sources. interactive media. More channels 2.

More Control
IPTV viewers can have more control over their television services. Figure 1. The customer can add and remove features when they desire.
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. this allows an IPTV service provider to offer thousands or tens of thousands of channels. Some channels may be provided free of charge while others require payment for viewing options. the channel is free and for other selections.Chapter 1
More Channels
To provide IPTV service. IPTV service providers simply connect (through a switch) to the media source that the viewer has selected at their distribution location. a service provider only needs to manage one connection between the end viewer and the media source (such as a television channel). All that is needed to provide highquality television channels is a media server.5 shows that Internet television offers virtually an unlimited number of media channels. This user has 148 units remaining for viewing channels this month. the available Internet television channels are shown along with the cost of accessing these channels. For some selections. Once a country has been selected. the user will be charged a fee (units of service in this example). Because IPTV channels can be routed through data networks (such as the Internet). IPTV systems can connect viewers to media sources and the media sources can be located anywhere in the world. a 2 Mbps to 4 Mbps data connection and a viewing device. They can choose from multiple service providers rather than a single television service provider that is located in their area.000 media channels. The viewer is first provided with the option to select which country to select. This example shows an Internet television service provider that offers access to more than 10. IPTV systems may allow the customer to setup their own IPTV service (instant activation) through a web page.

The Cheap TV
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. More IPTV Channels
Because IPTV has the capability of having multiple channels.6 shows how IPTV allows viewers to have more control over their television services. Figure 1.5.IPTV Basics
Figure 1. This example shows that a local telephone company offers television over a managed DSL connection which provides a guaranteed quality of service and access to local television channels. This diagram shows that the customer can select from several alternate service providers and Internet television systems have the capability of allowing new viewers to instantly subscribe to services and select features. it is possible to have multiple channels for each media program allowing intelligent filtering of content such as restricting channels with unacceptable video or audio.

administration.Chapter 1
provider offers access to many free channels throughout the world. IPTV systems have new capabilities that allow service providers to offer new services to viewers. The Premier TV company provides high quality television and access to movie channels. data. More Control over Television Services
More Services
Television service is the providing of television information to customers by a common carrier. or private operating agency using voice.6. IPTV systems deliver information that has been converted to a standard digital form. This allows IPTV systems to individually address video sources to specific users and to allow for interactive two-way services. Some of the
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Figure 1. and/or video technologies.

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. This example shows a program that allows the user to select the ending of a scene where a gunman is threatening a woman with a gun. This allows service providers to offer new media sources such as ads that are sent to specific viewers that have a matching profile or dynamic programs that allow the user to select or change the content that is presented to them. access games and community media centers. Viewers may be given access to public video (such as traffic video monitors) or private video (such as security video cameras at home and day care locations). and global television channels. This example shows that almost any type of digital media can be addressed to specific television devices and the viewer can interactively respond to prompts and initiate control requests (two-way capability). interactive multiplayer gaming.IPTV Basics
advanced services made possible for IPTV include addressable advertising messages. The user can select a happy ending (the girl gets away) or a sad ending (the girl gets shot). personal media channels.
How IPTV and Internet Television Systems Work
Understanding the basics of how IPTV and Internet television service works will help you make better choices and may help you to solve problems that can be caused by selecting the wrong types of technologies. advanced electronic programming guides. shopping channels. Two way control services could allow users to interactively search for programs they want to view. web commerce and advertising messages that offer the viewer a selection of options such as more information or to be redirected to an infomercial. Figure 1.6 shows how IPTV systems can provide new services that are not possible with traditional television systems. equipment and services.

the video and audio signals are converted into a digital form (digitization) and then compressing the digitized information into a more efficient form. To convert analog signals to digital form. If the video is in analog form.Chapter 1
Figure 1. Digitization is the conversion of analog signals (continually varying signals) into digital form (signals that have only two levels).
Digital Media Compression – Gaining Efficiency
Digital media compression is a process of analyzing a digital signal (digitized video and/or audio) and using the analysis information to convert the
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. the analog signal is sampled and digitized by using an analog-to-digital (pronounced A to D) converter.6.Converting Video Signals and Audio Signals to Digital Signals
A key first step in providing IPTV service is having the media in digital form. More Television Services
Digitization . The A/D converter periodically senses (samples) the level of the analog signal and creates a binary number or series of digital pulses that represent the level of the signal.

7 shows the basic digital speech compression process. The initial digitized bits represent every specific shape of the digitized word HELLO.
Figure 1. The digital compression process creates a sequence of frames (images) that start with a key frame. The key frame is digitized and used as reference
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. In this example. Digital media compression for IPTV includes digital audio compression and digital video compression.IPTV Basics
high-speed digital signals that represent the actual signal shape into lowerspeed digital signals that represent the actual content (such as a moving image or human voice).8 demonstrates the operation of the basic digital video compression system. Figure 1. Each video frame is digitized and then sent for digital compression. Digital Audio Compression
Figure 1. This process allows IPTV service to have lower data transmission rates than standard digital video signals while providing for good quality video and audio. the word “HELLO” is digitized. This digital information is analyzed and it is determined that this entire word can be represented by three sounds: “HeH” + “LeL” + “OH.” Each of these sounds only requires a few digital bits instead of the many bits required to recreate the entire analog waveform.7.

only the differences in images are transmitted. Packet Routing Methods Packet routing involves the transmission of packets through intelligent switches (called routers) that analyze the destination address of the packet and determine a path that will help the packet travel toward its destination.8. Digital Video Compression
Sending Packets
Sending packets through the Internet involves routing them through the network and managing the loss of packets when they can’t reach their destination.
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.Chapter 1
points for the compression process. This dramatically reduces the data transmission rate to represent a digital video signal as an uncompressed digital video signal requires over 270 Mbps compared to less than 4 Mbps for a typical digital video disk (DVD) digital video signal. Between the key frames.
Figure 1.

a destination address along with some description about the contents is added to each packet (called in the packet header). This descriptive information may include special handling instructions (called a label or tag) or priority status (such as high priority for real time voice or video signals). Routers regularly broadcast their connection information to nearby routers and they listen for connection information from neighboring routers. Routers may forward packets toward their destination simply based on their destination address or they may look at some descriptive information about the packet. Packet Transmission
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.9.9 shows how blocks of data are divided into small packet sizes that can be sent through the Internet. After the data is divided into packets (envelopes shown in this example). routers build information tables (called routing tables) that help them to determine the best path for them to forward each packet to. Figure 1. From this information.IPTV Basics
Routers learn from each other about the best routes for them to select when forwarding packets toward their destination (usually paths to other routers). As the packet enters into the Internet (routing boxes shown in this
Figure 1.

When the receiving end determines a packet is missing in the sequence.
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. the router can forward the packets to other routers that can forward the packet towards its destination. or through intentional discarding due to congested switch conditions. This example shows that several packets enter into the Internet. they can be reassembled into proper order using the packet sequence number. This example shows that because some packets will travel through different paths. it is common that packet retransmission requests are not performed and the lost packets simply result in distortion of the received information (such as poor video quality).Chapter 1
diagram). If a current path is busy or unavailable (such as shown for packet #3). Packet Losses and Effects on Television Quality Packet losses are the incomplete reception or intentional discarding of data packets as they are sent through a network. Packet losses are usually measured by counting the number of data packets that have been lost in transmission compared to the total number of packets that have been transmitted. The packets are forwarded toward their destination as usual. When the packets arrive at their destination. a lighting strike corrupts (distorts) packet 8 and it cannot be forwarded. from a lightning spike). each router reviews the destination address in its routing table and determines which paths it can send the packet to so it will move further towards its destination. Packet 6 is lost (discarded) when a router has exceeded its capacity to forward packets because too many were arriving at the same time. it can request that another packet be retransmitted. This diagram shows that the packets are serialized to allow them to be placed in correct order at the receiving end. Unfortunately. Figure 1. If the time delivery of packets is critical (such as for packetized video).10 shows how some packets may be lost during transmission through a communications system. Packets may be lost due to broken line connections.g. packets may arrive out of sequence at their destination. distortion from electrical noise (e.

The amount of packet buffering for IPTV systems can vary from tenths of a second to tens of seconds.IPTV Basics
Figure 1. a packet buffer may also be used in the sending device to allow the rapid selection and retransmission of packets when they are requested by the receiving device. While a packet buffer is commonly located in the receiving device.
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. Packet buffering is commonly used in IPTV systems to overcome the transmission delays and packet losses that occur when viewing IPTV signals. A packet buffer receives and adds small amounts of delay to packets so that all the packets appear to have been received without varying delays.10. Packet Losses
Packet Buffering Packet buffering is the process of temporarily storing (buffering) packets during the transmission of information to create a reserve of packets that can be used during packet transmission delays or retransmission requests.

some of the packet transmission time varies (jitter) and some of the packets are lost during transmission.11 shows how packet buffering can be used to reduce the effects of packet delays and packet loss for streaming media systems.11. This diagram shows that during the transmission of packets from the media server to the viewer. Packet Buffering
Converting Packets to Television Service
IPTV data packets are converted back to television signals via gateways. Gateways may interconnect IPTV service to a television network (such as a hotel television system) or they may convert the signals directly to a television signal format (such as a NTSC or PAL analog television signals).Chapter 1
Figure 1. The packet buffer temporarily stores data before providing it to the media player.
Figure 1.
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. This provides the time necessary to time synchronize the packets and to request and replace packets that have been lost during transmission.

Middleware controls the media servers and gateways that provide media to the viewing devices. This example shows that the gateway must convert audio. This example shows that the media gateway receives requests to view information (the user or network sends a message to the media gateway).12 shows how a media gateway connects a television channel to a data network (such as a broadband Internet connection).
Managing the Television Connections
Middleware software controls the setup. IPTV systems manage the downloading or streaming of IPTV signals to the consumer and may manage the selection (switching) of the media source. feature operation. and control information. video and control signals into a format that can be sent through the Internet. These digital signals are then analyzed and compressed by a coding processor. The gateway may have a database (or access to a database) that helps it determine authorized users and the addresses to send IPTV signals. the media gateway usually has available several different types of coding devices. Because end users may have viewers that have different types of coders (such as MPEG and AAC). A television gateway usually has more intelligence (processing function) than a data network bridge as it can select the video and voice compression coders and adjust the protocols and timing between two dissimilar computer systems or IPTV networks. and disconnection of television channels connected through the data network. connection. Figure 1. While there is one communication channel from the gateway to the end viewer.IPTV Basics
Gateways (Adapters) Connect the Internet to Standard Televisions A television gateway (an adapter box) is a communications device or assembly that transforms audio and video that is received from a television media server (IPTV signal source) into a format that can be used by a viewer or different network. audio.
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. The gateway first converts video and audio signals into digital form. the communication channel carries multiple media channels including video.

One of the key advantages of downloading is that the data transmission rate can vary and operate at any speed. If the user is willing to wait long enough. Figure 1. Download commonly refers to retrieving complete files from a web site server to another computer. Key disadvantages to downloading are the need to wait until the entire file is transferred before being able to view and the need to have enough storage room to hold the entire video (about 4 GB for a 2 hour movie).12. This diagram shows how the web server must transfer the entire media file to the media player before viewing can begin.
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. IPTV Gateways
Downloading Downloading is the process of transferring a program or a data from a computer server to another computer. Downloading movies requires the storage of the entire file on a hard disk or other type of memory storage for playback at a later time.Chapter 1
Figure 1. the entire file can be downloaded for future playback on any connection.13 shows how to download movies through the Internet.

Downloading Movies through the Internet
Streaming Streaming is a process that provides a continuous stream of information that is commonly used for the delivery of audio and video content with minimal delay (e.
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.13. This diagram also shows that the streaming process usually has some form of feedback that allows the viewer or receiving device to control the streaming session and to provide feedback to the media server about the quality of the connection.g. Figure 1. Streaming signals are usually compressed and error-protected to allow the receiver to buffer. This diagram shows that streaming allows the media player to start displaying the video before the entire contents of the file have been transferred. decompress. real-time).14 shows how to stream movies through an IP data network. and time sequence information before it is displayed in its original format. This allows the media server to take action (such as increase or decrease compression and data transmission rate) if the connection is degraded or improved.IPTV Basics
Figure 1.

When the user desires to access these media sources.15 shows how a basic IPTV system can be used to allow a viewer to have access to many different media sources. Figure 1. This diagram shows that the user only needs one video channel to the SVS to have access to virtually an unlimited number of video sources. When the media connection is set up directly between the media server and the viewer.Chapter 1
Figure 1. IPTV Streaming
Switching (Connecting) Media Channels IPTV systems may set up connections directly between IPTVs or IP set top boxes and media servers or it may use a video switching system to connect the viewer to one of several available media sources. subscription services. This diagram shows how a standard television is connected to a set top box (STB) that converts IP video into standard television signals.14. the control commands (usually entered by the user by a television remote control) are sent to the SVS and the SVS determines which media source the user desires to connect to. this is known as soft switching. The STB is the gateway to an IP video switching system. and movies on demand.
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. This example shows that the switched video service (SVS) system allows the user to connect to various types of television media sources including broadcast network channels.

IPTV Connection
Multiple IPTVs per Home
Each household may have several users that desire to watch different programs. This diagram shows 3 IPTVs that
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. This requires the bandwidth to be shared with each individual IPTV. set top boxes or IPTVs in each home. Households may have a combination of several multimedia computers. the bandwidth of each IPTV signal must be added.IPTV Basics
Figure 1. Figure 1.16 shows how much data transfer rate it can take to provide for multiple IPTV users in a single building. When viewers are watching television channels (different channels).15.

8 Mbps to 3.8 Mbps to receive an IPTV channel.Chapter 1
require 1. IPTV channel transmission may be exclusively sent directly to a specific viewer (unicast) or it may be copied and sent to multiple viewers at the same time (multicast)
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. This means the broadband modem must be capable of providing 5.4 Mbps to 11.
Figure 1.4 Mbps to allow up to 3 IPTVs to operate in the same home or building. IPTV Multiple Users
Transmission
IPTV channel transmission is the process of transferring the television media from a media server or television gateway to an end customer.16.

17 shows how IPTV systems can deliver the same program to several users using unicast (one-to-one) channels. IPTV Unicast Transmission
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. Because each viewer is receiving 3 Mbps. The use of unicast transmission is not efficient when many users are receiving the same information at the same time because a separate connection for each user must be maintained. the media server must have a connection that can provide 9 Mbps (3 Mbps x 3 viewers). This example shows that each viewer is connected directly to the media server.IPTV Basics
Unicast Unicast transmission is the delivery of data to only one client within a network. If the same media source is accessed by hundreds or thousands of users. Unicast transmission is typically used to describe a streaming connection from a server to a single client.
Figure 1. Each user is given the same address to connect to when they desire to access that media (such as an IPTV channel).17. Unicast service is relatively simple to implement. Figure 1. the bandwidth to that media server will need to be hundreds or thousands of times larger than the bandwidth required for each user.

Because of the complexity and cost issues. many Internet routers do not implement multicast transmission. The implementation of multicast systems is generally more complex than unicast systems as more control is required to add and remove members of multicast groups. As a multicast signal travels through a communication network. Multicast systems form distribution trees of information.g. Figure 1. When the first movie watcher requests the movie. For multicast systems to operate. routers) that copy the information form the branches of the tree. nodes (routers) within the network must be capable of multicast sessions. When the movie is trans-
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. all the nodes within the network can be setup and controlled for multicast transmission. Nodes (e. routers) to receive and retransmit the same signal to multiple receivers. it is requested from the telephone end office.g. This example shows that end users who are watching a movie that is initially supplied by media center that is located some distance and several switches away from end users (movie watchers). The interconnection switch also determines the movie is not available in its video storage system and the movie is requested from the distant media source. it is copied at nodes within the network for distribution to other nodes within the network.18 shows how an IPTV system can distribute information through a switched telephone network. If the multicast network is controlled by a single company (such as a DSL or cable modem data service provider).Chapter 1
Multicast Multicast transmission is a one-to-many media delivery process that sends a single message or information transmission that contains an address (code) that is designated to allow multiple distribution nodes in a network (e. The telephone end office determines that the movie is not available in its video storage system and the end office switch requests the movie from the interconnection switch. Multicast recipients generally submit requests to a nearby node within a multicast network to join as part of an active multicast session. The use of multicast transmission can be much more efficient when the same information is sent to many users at the same time.

This program distribution process reduces the interconnection requirements between the switching distribution systems. IPTV Multicast Transmission
Viewing IPTV
IPTV media can be viewed on a multimedia computer. or on a dedicated IPTV. standard television using an adapter. the interconnecting switches may make a copy for future distribution to other users.18.
Figure 1.
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.IPTV Basics
ferred from the media center to the end customer.

stop. process compressed media signals. IPTV signals may be able to be displayed on a multimedia provided it has enough processing power (processing speed) and the necessary media player protocols and signal decompression coders.
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. the control protocols (e. decoded and processed. This may result in pixilation (jittery squares) or error boxes. commands for start. These signals must be received. and manages the call connection. accessories (such as a handset). data and video. The media player software controls the sound card.Chapter 1
Multimedia Computer
A multimedia computer is a data processing device that is capable of using and processing multiple forms of media such as audio. maintain a connection. Because many computers are already multimedia and Internet ready. This may become more apparent when IPTV is taken from its small format to full screen video format. Just because the media player can receive and decode digital video and digital audio signals. Full screen display requires the processor to not only decode the images but also to scale the images to the full screen display size. IPTV signals contain compressed audio and video along with control protocols. A media player must also have compatible control protocols.g. it is often possible to use a multimedia computer to watch IPTV through the addition or use of media player software. and process television control features. or external telephone accessory device (such as a remote control) that can be connected to the computer through an adapter (such as an infrared receiver). Control of IPTV on a multimedia computer can be performed by the keyboard. and play) may be in a protocol language that the media player cannot understand. The media player must be able to find and connect to IPTV media servers. The processing power of the computer may be a limitation for receiving and displaying IPTV signals. Using a video accelerator card that has MPEG decoding capability may decrease the burden of processing video signals. mouse.

IP televisions also include the necessary software and hardware to convert and control IPTV signals into a format that can be displayed on the IP television (e. IP set top boxes are commonly located in a customer’s home to allow the reception of IP video signals on a television or computer. IP televisions contain embedded software that allows them to initiate and receive television through IP networks using multimedia session protocols such as SIP.IPTV Basics
IP Set Top Boxes (IP STB)
An IP Set Top box is an electronic device that adapts IP television data into a format that is accessible by the end user. and may have restricted access to Internet services.g. limited displays. channel 3). The output of an IP set top box can be a television RF channel (e. An IP STB is basically a dedicated mini computer which contains the necessary software and hardware to convert and control IPTV signals. video and audio signals or digital video signals. Multimedia mobile telephones contain embedded software that allows them to initiate and receive multimedia communication sessions through the
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. An IP television has a data connection instead of a television tuner.g. IP STBs must convert digital broadband media channels into the television (audio and video signals) and decode and create the necessary control signals that pass between the television and the IPTV system. Mobile telephones have limited information processing power. picture tube or plasma display).
IP Televisions
IP televisions are display devices that are specifically designed to receive and decode television channels from IP networks without the need for adapter boxes or media gateways.
Mobile Video Telephones
Mobile telephones with multimedia capabilities may be able to watch television channels.

mobile telephone media players in mobile telephones may use compression and protocols that are more efficient than are used by standard IPTV systems. Because of the limited bandwidth and higher cost of bandwidth for mobile telephones.
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Internet. To increase the efficiency. This may cause some incompatibilities or unexpected operation for mobile television systems. mobile telephone data sessions may be connected through gateways that compress media signals and convert standard control protocols to more efficient and robust control protocols.

IPTV Basics
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IPTV can provide advanced features and services that are not possible with traditional broadcast television systems. television) to customers by a common carrier.Chapter 2
IPTV Services and Features
IPTV services are the providing of multimedia services (e. administration. community content and personal media channels. syndicates and local stations along with new content sources such as international (global) programs. Television programming may be live. data. and/or video technologies. sponsored programs. IPTV television programming sources include traditional broadcast sources such as television networks. scheduled or on-demand programming.
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Television Programming
Television broadcast services are the transmission of television program material (typically video combined with audio) that may be paid for by the viewer and/or by advertising.g. Scheduled programming is the providing of television programs in a pre-selected time sequence. Live television broadcasting is the transmission of video and audio to a geographic area or distribution network in real time or near-real time (delayed up to a few seconds). On demand programming is providing or making available programs that users can interactively request and receive. or private operating agency using voice. In addition to providing the basic television services and features.

Company television may be produced for the public and/or for internal communication purposes. powerful security system processing in a server. Traditional (legacy) security systems use proprietary sensing and transmission equipment. vendors or others who are provided with access may distribute company television programs to monitors within company buildings or for distribution to multimedia computers that are only accessible by company employees. Public company television channels may provide information about products. multi-user network gaming or gambling. and wide area connectivity (such as through the Internet).IPTV Basics
Enterprise (Company) Television
Enterprise programming is media that is created and managed for viewing by a company or for visitors it authorizes to view its programming content. 32
. Video surveillance is the capturing of video for the observation of an area or location at another location. online gaming service. and have interconnections that are limited to local geographic areas. water hazard.
Security Monitoring
Security systems are monitoring and alerting systems that are configured to provide surveillance and information recording for protection from burglary. have limited control processing capabilities. Gaming services provided by IPTV systems may include game program distribution (downloading games). services or applications of the products or services that are of interest to the public. fire. Employees. Internal (“in-house”) company television programs may be used to provide employees with educational and company specific information (such as the location of a company meeting or party). The use of IPTV systems connected through standard data networks allows for the sending of media (such as digital video).
Gaming
Gaming is an experience or actions of a person that are taken on a skill testing or entertainment application with the objective of winning or achieving a measurable level of success. and other types of losses.

1 shows how a variety of security accessories can be integrated into an IPTV based communication system.1. This example shows how a police station can monitor multiple locations (several banks) through the addition of digital video and alarm connections. Because the images are already in digital format. IPTV Security Monitoring
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. it may be possible to send these pictures to police cars in the local area to help identify the bank robbers. This example shows that when a trigger alarm occurs at a bank (such as when a bank teller presses a silent alarm button). These monitoring systems can be owned an operated by the IPTV system operator or they can be monitoring stations operated and managed by other companies (such as police station central monitoring facilities).. Figure 2.Chapter 2
IPTV access devices (such as set top boxes) may contain connection points (such as USB connections) that allow for digital video signals to be sent through the IPTV system to a monitoring system.
Figure 2. the police can immediately see what is occurring at the bank in real-time.

services.2 shows how IPTV advertising messages can be in the form of interstitial broadcast messages. One of the most complicated areas for IPTV can be the management of advertising services. An interstitial ad is an advertising message that is inserted “in between” program segments. Advertising management is the process of creating. Mixed media advertising is the combining of advertising media along with other video and text graphics on a television or video monitor. mixed media messages or interactive ads. and options offered by a company. An advertising program typically begins by setting up advertising campaigns. In example A.IPTV Basics
Advertising
Advertising is the communication of a message or media content to one or more potential customers. Because advertising services on IPTV systems can range from broadcast advertising (to all people in a geographic area) to customized addressable advertising (custom ads for specific viewers). mixed media or interactive media. Advertising campaigns define the marketing activities such as the specific advertising messages that will be sent to customers who are classified into certain categories (target market segments) about products.
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. Interactive advertising is the process of allowing a user to select or interact with an advertising message. Advertising messages may be in the form of interstitial. advertising management can be a complex but yet a very profitable process. Figure 2. presenting. Interstitial ads can also be popups (when selecting a new channel) and pop-downs (when exiting a selected program). Example C shows how an advertising message my change based on the selections of the viewer. Example B shows how an advertising message may be overlapped or merged into the underlying television program. a network operator provides a program with advertising messages already inserted (interstitial) into the program. purchasing and reporting of advertising programs. managing.

processing and payment of orders.3 shows how a television program can use mixed media to provide product offers to qualified consumers at specific times in a display location that is noticeable but not intrusive. exchanging of order information between companies in near real-time and the ability to offer multiple forms of payments that may be collected by different companies. The processes that used in t-commerce include advanced product offering catalogs (video catalogs). order processing.Chapter 2
Figure 2. Key issues for IPTV t-commerce billing include transferring accounting records through multiple systems that transfer between multiple companies that allow for presentation. Types of IPTV Advertising Messages
Television Commerce (T-Commerce)
Television commerce (t-commerce) is a shopping medium that uses a television network to present products and process orders. This picture shows that during a news
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.2. Figure 2.

g. This means that t-commerce systems will likely offer management portals. the viewer is presented with a pizza icon from a local pizza restaurant.IPTV Basics
program.3.
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. configure their presentation options for the product (e.
Figure 2. Offer management portals will allow the vendor to add new products. mixed media) and define the product or service offers for specific market segments. Television Commerce
Vendors of products that are sold on IPTV systems may be allowed to directly interact with their product offers as they know their customers better than IPTV service providers. This example shows that when the user selects the icon. a small window appears with the pizza offer details.

Network Programming
Network programming is the selection of shows and programs that are offered by a television network provider. These programs are distributed to network affiliates (local broadcasters) along with advertising commercials that is sold by the network and/or local broadcaster. local. An example of a local program is a news program that is created and broadcasted by a local broadcaster.
Local Programming
Local programming is the selection of shows and programs that are offered by a local television network provider. community and personal content.
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. syndicated. sponsored.Chapter 2
IPTV Content
IPTV content is a mixture of rich media programming that includes television and other forms of content. Some of the common forms of IPTV content include network.
Syndicated Programming
A syndicated program is a media session (such as a television show) that is distributed by an organization to more than one broadcasting company. An example of a syndicated program is a television show that is developed independent of the networks and is made available to multiple television broadcasting companies. An example of a network program is a television series that is developed and owned by a television network.

Examples of personal content include pictures of friends.IPTV Basics
Sponsored Programming
Sponsored content is specialty programs or media that are paid for by people or companies who are looking to promote a specific solution or to develop a mailing list of the viewers who watch the content (similar to sponsored web seminars). Examples of community content include school.
Community Content
Community content programming is media that is created and managed by members of a community or a group that can be viewed by others who are interested in community content. sports and local events that members of a community have an interest in. Community members are commonly interested in assisting in the creation.
Personal Media
Personal content is media or data that is created and managed by an individual. management and delivery of the community content with or without direct compensation.
International Programming
International programming is the selection of shows and programs that are offered by sources outside the country that is offering the television service. The individual owner or user of personal content may establish a hierarchy of viewing rights that can vary between family.
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. video clips at events and creative images. An example of a global program is a news program that is created and broadcasted from another country. close friends or lists of specific individuals or channel types.

interactive television control. “How to Install Tile”). advanced channel selection options.
Flat Tail Content
Flat tail content is program media that has a relatively consistent viewing demand over a period of time. addressable advertising.
Long Tail Content
Long tail content is programs or media that is initially viewed or desired by a large group of people and then has a much lower interest and viewing level that occurs over a relatively long period of time. ad bidding. Long tail typically refers to the statistical distribution of valuable products or content where a majority of usage or distribution occurs at the beginning of a process or product offering. interactive program guides. personal media channels. t-commerce order processing and user profiling.g. An example of flat tail content is an instructional painting lesson (e. the “Painting in Watercolors”) or a home repair show (e. Flat tail content is programs such as educational or personal development programs that provide enriching information to viewers when they need that information.Chapter 2
IPTV systems offer cost effective access to any type of program including programs that have a very high initial interest (long tail content) and programs that have a low interest level for an extended period of time (flat tail content). additional people begin to need this information which results in the continuous demand for flat tail content. As time passes. global television channels. anywhere television service. everything on demand. ad telescoping. real time billing.
IPTV System Features
IPTV system features include instant activation.g.
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.

4. such as a billing address and method of payment.
Figure 2.IPTV Basics
Instant Activation
Instant activation is a process that allows users to obtain service immediately after applying for service. account identification codes can be provided manually to the user or they may be automatically entered into the IPTV viewer. In this example. IPTV Instant Line Activation
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.4 shows how it is possible for a user or company system administrator to instantly activate a new IPTV service. After the user has provided the necessary information. the ITVSP has created a web access page that allows the user to self activate themselves. Figure 2. The user can then select feature preferences such as preferred television channels and viewer profile. Instant activation may use the same data connection for requesting and activating communication services as for the transfer of the required services and features.

In this example. This example shows how the IPTV service provider keeps track of each channel (or premium channel used).Chapter 2
Real Time Accounting and Billing
Real time accounting and billing is the process of gathering. IPTV service commonly allows for real time billing for tracking of IPTV services. and displaying (posting) of account information either at the time of service request or within a short time afterwards (may be several minutes).
Figure 2.5 shows how IPTV service can provide real time accounting and billing records immediately after they are created (in real time). Figure 2.5. these charges or usage amounts can be displayed immediately through on the IPTV viewer or through an Internet web page. It uses the television channel setup and termination information to adjust the accounting and billing information. IPTV Real Time Accounting and Billing
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. rating.

time period.IPTV Basics
Channel Selection (Program Guides)
IPTV channel selection is the process of finding and connecting to an IPTV data address (IP address) so it can receive and decode a television or media channel. show title. Because it is difficult for viewers to remember or organize URLs and IP addresses. actor name. IPTV service providers (ITVSPs) offer many new ways to find and select television channels. this example shows that there are several new more effective ways to search and select channels. IPTV service providers provide a selection screen or device that allows users to find and select IPTV channels. While it is possible for IPTV systems to use channel numbers for the selection of IPTV channels. The user can also select from the channel numbers offered by their IPTV provider. the viewer may not be authorized to connect to the channel at that address. Authorization codes are typically preestablished by viewers or companies that provide IPTV services to viewers. Figure 2. country. The user can search for channels by favorites. EPGs can vary from simple program selection to interactive filters that dynamically allow the user to filter through program guides by theme. Owners of IPTV media can restrict access to paying customers. or other criteria. network provider and category. It is possible for viewers to direct connect to IPTV channels if they know the URL or IP address (web link). Although the viewer may have the address or the URL of the IPTV channel (a media server). While it is possible to have IPTV service that uses channel numbers that are identical to standard cable television systems. network names and show titles. channel selection screens usually have more descriptive information such as channel numbers. IPTV service providers usually provide an electronic programming guide (EPG) as an interface (portal) that allows a customer to preview and select from possible lists of available content media. Viewers are also able to connect to IPTV channels through the use of a web link on web pages or through a link that is sent (embedded) in emails.6 shows some of the different ways a user can find and select IPTV channels.
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.

and “video-on-demand” (VOD). Internet access. and games. home banking. television extensions have a fixed
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. home shopping. email. These connections may be shared (several televisions on the same line) or they may be independently controlled (such as in a private television system). Interactive television has three basic types: “pay-per-view” involving programs that are independently billed. enabling request for a particular film to start at the exact time of choice. Interactive television offers interactive advertising. IPTV Channel Selection
Interactive Television (iTV)
Interactive television is the providing of video services that allows for the user to control part or all of the viewing experience.Chapter 2
Figure 2.
Anywhere Television Service (TV Roaming)
Television extensions are viewing devices that are connected to a television distribution system. Traditionally.6. “near video-on-demand” (NVOD) with groupings of a single film starting at staggered times.

If this person takes their IPTV viewer (possibly a laptop) to a hotel in New York that has a broadband connection. When an IPTV viewer is first connected (plugged-in) to a data connection. in the office. In essence. or in a hotel. they can use different types of viewers such as multimedia computers (laptops).IPTV Basics
wire or a connection line. standard televisions with adapter boxes and IPTVs. at home.7 shows how Internet Televisions can be used anywhere in the world where they can be connected to an Internet connection. In this example. The IPTV service provider manages user accounts and sets up connections between users and media sources. it requests the assignment of a temporary Internet address from the data network. It doesn’t really matter where the IPTV is plugged in. This allows a television viewing device to either share (directly connect to) another communication line or to allow it to independently connect it to a switching point (such as a private company Television system). As long as the Internet television user has a valid Internet television account. What makes this so interesting is that IPTVs can be taken anywhere and they will continue to operate as if there were no changes. this allows IPTVs to operate at any connection point that is willing to provide it broadband access to the Internet. when they plug the IPTV viewer into the Internet in New York. a user subscribes to Internet television service from an IPTV service provider in Singapore. Because the ITVSP always knows the current Internet address that is assigned to the IPTV each time it has been connected to the Internet. It uses this Internet address to register with the ITVSP after it has been connected to the Internet. Suppose a person in Singapore subscribes to local television services in Singapore. It does this because the IPTV registers with the IPTV service provider when it is plugged into the Internet. Figure 2. The Internet address of each IPTV is dynamically assigned each time they are turned on and the IPTV system keeps track of these addresses.
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. This diagram shows that an Internet television user can obtain television service at different locations such as at an airport. this allows an IPTV to operate like a television extension that can be plugged in anywhere in the world. it will operate just as it was in their home in Singapore.

8 shows how IPTV allows a person to view television channels in other cities. IPTV channels that are delivered through the Internet typically can be viewed at any location in the world that offers broadband data access. states. The ability of IPTV systems to provide video service to outside their local (often regulated) areas allows for new competition. In this example. Internet Television Extensions go Anywhere in the World
Global Television Channels
Global television channels are TV channels that can be viewed anywhere in the world. or countries. He then selects the channel source
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. This diagram shows that the viewer connects his multimedia laptop to a broadband connection and logs into his Internet television service provider with his access codes. Figure 2. a viewer from the United Kingdom is traveling to the United States and he desires to watch a soccer game in Australia.Chapter 2
Figure 2.7. The typical cost for viewing global television channels is the content media access costs (such as a fee for a movie) and the broadband data access cost (a monthly broadband access charge).

viewer) to select and view media (typically video or music) from a variety of media sources. An example of how a PMC may be used for IPTV is the control and distribution of mixed media (such as digital pictures and digital videos) through a personal television channel to friends and family members.8. The viewers ITVSP provider is located in the UK. The user can upload media to their personal media channels and allow friends and family to access pictures and videos of family members and gatherings via their IPTVs.
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. When the ITVSP receives and authorizes the request.g. The media gateway then sends the information directly to the viewer through the Internet. Using Internet Television to view International Television Channels
Personal Media Channels (PMC)
A personal media channel (PMC) is a communication service that allows a media user (e.
Figure 2.IPTV Basics
and quality of image he desires (the rates increase for higher quality access). An IPTV customer may be assigned a personal television channel. it sends an authorization message to a media gateway in Australia that is converting the video from the sports event to a data format that can be sent through the Internet.

This example shows how an IPTV user “Bob” is uploading pictures from a party to his personal media channel 9987.9.
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.
Figure 2. The use of addressable advertising allows for rapid and direct measurement of the effectiveness of advertising campaigns. The address of the customer may be obtained by searching viewer profiles to determine if the advertising message is appropriate for the recipient.Chapter 2
Figure 2.9 shows how personal media channels allow other viewers to be given access to specific types of personal media on their IPTV. Personal Media Channels
Addressable Advertising
Addressable advertising is the communication of a message or media content to a specific device or customer based on their address. People on his list of viewers who also have IPTV service can select Bobs television channel 9987 and see the pictures. This example shows that the personal media channel can have restrictions on who can view the personal media channel.

viewers will typically want to select their programming name.10. It also allows the advertiser to test a number of different ads in the same geographic area at the same time. Figure 2. Because the programming name has a profile (preferences). Because of the advanced features offered by IPTV such as incoming calls/emails and programming guides that remember favorite channels. The ability to send ads to a specific number of viewers allows advertisers to set specific budgets for addressable advertising.IPTV Basics
A key aspect of addressable advertising is the validation of the viewer. The potential revenue for addressable advertising messages that are sent to viewers with specific profiles can be 10 to 100 times higher than the revenue for broadcasting an ad to a general audience. This diagram shows that a media program (such as a television show or movie) is being
Figure 2. Addressable Advertising
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. IPTV systems may ask (prompt) the viewer to select their name from a list of registered users in the home when the IPTV is turned on. advertising messages can be selected that best match the profile.10 shows how addressable advertising can be used to better match advertising messages to the wants and needs of viewers.

Everything on demand services include video on demand (VOD). The viewer may be provided with options of immediately viewing the expanded ad or bookmarking an ad for later viewing.Chapter 2
sent to 3 homes where the televisions in each home have a unique address. the channel source is redirected to a longer (expanded) advertising message. a separate advertising message is sent to each one of the viewers based on the address of the television. near video on demand (NVOD) and time shifted programming. If the ad is expanded. This diagram shows that a viewer is presented with an ad that can be expanded to provide more information.
Ad Telescoping
Telescoping advertisements are extended advertising messages (selected or automatically expanded) from a smaller and/or shorter version of an ad to a larger and/or longer version of an ad. Figure 2.11 shows how ads can be expanded using ad telescoping. If the viewer selects the more button. their current viewing point in the television program may be stored so they can return to the exact point they left when they selected to view the expanded ad (time shifting).
Everything on Demand (EoD)
Everything on demand is a service that provides end users to interactively request and receives media services of any type. Ad telescoping allows the viewer to immediately obtain more information about a product or service by selecting an interactive option on the advertising message.
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. When the time for a 30 second commercial occurs. These media services may come from previously stored media (entertainment movies or education videos) or they may have a live connection (news events in real time). This allows each viewer to receive advertising messages that are better targeted to their needs and desires.

These video services are from previously stored media (entertainment movies or education videos) or have a live connection (news events in real time). Near video on demand is a video delivery service that allows a customer to select from a limited number of broadcast video channels when they are broadcast.11.12 shows how IPTV can allow a viewer to request control of the presentation of television programs on demand. Figure 2. Ad Telescoping
Video on demand is a service that provides end users to interactively request and receive video services. This allows the viewer to scan through a list of programs that they have not previously viewed. NVOD channels have pre-designated schedule times and are used for pay-per-view services. this IPTV service provider informs the viewer of which pro50
. In this example. This diagram shows that a television on demand viewer can browse through available television channels. EoD can be enhanced by advanced electronic programming guides that maintain a history of previously viewed television or media shows.IPTV Basics
Figure 2.

Figure 2. it may be possible to separately bid for different age groups. For example. When the user selects a potential program to view. Bidding for IPTV systems is likely to occur for particular segment types. Ad bidding requires a bid management process that can monitor and adjust the bid amounts for the requested insertion and placement of ad messages. a short description of that program is shown at the bottom of the screen along with the cost for viewing that particular program.12. it may be possible to determine which segment the viewer belongs to.Chapter 2
grams they have already viewed and the length of time each program will run. if each view-
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. Everything on Demand
Ad Bidding
Ad bidding is the process of selection of threshold amounts that may be paid for the insertion of advertising messages. An example of ad bidding is the paying for ad listings on search engines such as Google or Yahoo. Because IPTV systems can interact with the viewer. For example.

geographic regions. This example shows that the advertiser may also be able to select if the same ad should be sent to the same person more than one time. number of click through selections. it is likely that the actual viewer and their characteristics can be determined. To help companies determine the success of their advertising campaigns. the number of ad expansions and the number of ad compressions. income ranges. program types. This example shows that IPTV advertisers may bid for ads that may appear on a variety of programs throughout various geographic regions. Ad Bidding
Measuring the performance and success of an advertising program can be accomplished through the use of existing and new types of marketing measurements including ad impressions. IPTV advertising reports may include the number of ad impressions per segment.13 shows how IPTV ad bidding may work for selling cars. This diagram shows that bidding for advertising messages may occur for particular age groups. ad selections. 52
. The advertiser sets the maximum bid they are willing to offer and a maximum number of impressions that may be selected to ensure advertising budgets can be maintained. advertising reports are tables.IPTV Basics
er in a household is provided with a login choice so they can customize their interface (TV screen saver) and access their preferred channel list (MTV compared to Discovery Channel). ad expansions and ad compressions.
Figure 2.13. Figure 2. graphs or images that may be provided to represent specific aspects of advertising campaigns or the information or data that is created from advertising campaign.

Figure 2. which allows a user to select or interact with an advertising message.
FFigure 2. IPTV offers the opportunity for interactive advertising.
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. This interaction may result in a redirecting of the source of an advertising message to play a longer more informative version of the ad (expanded ads). Ad selections are indicated by the click through rate (usually in percentage form). which is a ratio of how many selections (red button) or clicks (mouse selections) an advertising message or item within the ad message receives from visitors compared to the number of times the advertising message is displayed. An example of click through rate for an ad button that is clicked 5 times out of 100 displays to visitors is 5%. This example shows that an advertiser has selected to advertise to three age groups. Viewers may also be able to end an advertising message to return to their media program (compressed ads).Chapter 2
An ad impression is the presentation of an advertising message or image to a media viewer.14.14 shows a sample report that may be generated for IPTV interactive advertising. Ad selections are the clicking or indication that a button or attribute on an advertising message has been selected. IPTV Advertising Reporting
T-Commerce Order Processing
Television commerce order processing is the steps involved in selecting the products or service from a television catalog or advertising and agreeing to the terms that are required for a person or company to obtain products or services.

Fulfillment is the process of gathering the products and materials to complete an order and shipping the products or initiating the services that were ordered. the items are removed from their shopping cart until they start shopping again. This diagram shows that order status information may be provided from the vendor to the TV service provider and this infor-
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. Once they have completed the purchase. This example shows that a viewer is presented with a product offer (a pizza).IPTV Basics
For t-commerce systems. This offer is associated with an offer identification code to allow the user to select the offer and to be redirected to an order window. IPTV order fulfillment can range from the immediate delivery of media products (such as games or television programs) to the delivery of products over an extended period of time (such as an order of books that has a mix of available and future ship dates). the order information is sent to the vendor (the pizza restaurant) where it is confirmed. Order processing is the defining of terms that are agreeable to the viewer for the acquisition of a product or service. Customers will likely associate responsibility for fulfilling the order to the TV service provider. Depending on the types of products and services offered. company or other person who is involved with an order to gather information as to the status of the processing of the order. Another important part of the t-commerce system is the fulfillment process. Figure 2. When the user completes the order. The online shopper is typically allowed to view and change items in their shopping cart until they purchase. after a viewer has selected a product offer. t-commerce systems may include order tracking capability. To reduce the cost of customer care and to avoid potential negative conflicts for unfulfilled products. It is important that the t-commerce system identify the particular user as there can be several users in a household that share an IPTV and each may have orders in progress with a variety of vendors. Selected products are placed in a shopping cart for the particular user. Order tracking is the ability of a customer.15 shows a typical scenario of t-commerce order processing. order processing occurs. Shopping carts are the electronic containers that hold online store items while the user is shopping.

Payment processing is the tasks and functions that are used to collect payments from the buyer of products and services. direct payment collec-
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. When the order is complete. Television Order Processing
T-commerce orders can have a variety of payment methods that may need to be recorded in near real time to ensure the vendor and the t-service provider receive payment when the provide products or services.
Figure 2. the vendor provides information to the TV service provider that the order has been filled to allow the order record to be marked as completed.Chapter 2
mation may be used to update the customer about the status of the order (pizza cooking). Payment systems may involve the use of money instruments.15. or other form of compensation used to pay for one or more order invoices. T-commerce payment options include payment on the television bill. credit memos. coupons.

16.IPTV Basics
tion by the vendor. Figure 2. order status and payment information. bill to 3rd party or pay using other payment options.16 shows how a vendor may receive a t-commerce order report. a standardized billing communication system is necessary. This billing system will need to transfer a variety of event information including order details. the customer may be able to place the order on their television bill or the customer may use a 3rd party such as Paypal to pay for the transaction. It is likely that t-commerce will offer a mixed set of payment options to the viewer.
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.
Figure 2. This example shows that a t-commerce vendor may receive payment from a t-commerce customer directly by cash or a credit card transaction. T-Commerce Payment Options
To allow multiple companies to process orders with multiple TV service providers.

IPTV service offers the possibility for recording and using viewer information to better target services to users.
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. measuring and analyzing usage characteristics of a user of a product or service. An example of user profiling is the offering of movie service packages (such as 5 films for children at a discount price) that is based on the previous viewing habits (such as watching 5 children’s movies in the past 2 weeks).Chapter 2
User Profiling
User profiling is the process of monitoring.

IPTV Basics
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.

transfers the packets through a packet data network. recombines the packets and extracts the digitized audio.1 shows how video can be sent via an IP transmission system. codes and/or compresses the data. receiving.1. coding. addressing.Chapter 3
Introduction to IP Video
IP video is the transfer of video information in IP packet data format. decoding and converting (rendering) IP video data into its original video form. adds IP address information to each packet. decodes the data and converts the digital audio back into its original video form. IP Video System
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.
Figure 3. Transmission of IP video involves digitizing video. Figure 3. transferring. This diagram shows that an IP video system digitizes and reformats the original video.

Figure 3.
Frame Rates
Frame rate is the number of images (frames or fields) that are displayed to a movie viewer over a period of time. for example to one of 256 24-bit colors. Vertical resolution usually is expressed as the number of distinct horizontal lines that can be seen. Horizontal resolution usually is expressed as the number of distinct pixels or vertical lines that can be seen in the picture. Frame rate is typically indicated in frames per second (fps). a color palette may be used to map each value to one of a small number of more precisely represented colors. and therefore has a higher resolution capable of reproducing more detail in an image. For a low color depth like 8 bits per pixel. Pixels can range in size and shape and are composed of color (possibly only black on white paper) and intensity. Pixel color depth is the number of bits per pixel that is used to represent color.IPTV Basics
Resolution
Resolution is the number of image elements (pixels) per unit of area. a color image that uses 8 bits for each color uses 24 bits per pixel.2 shows how the resolution of a video display is composed of horizontal and vertical resolution components. A display with a finer grid contains more pixels. Pixel depth is the number of bits per pixel that is used to represent intensity and color.
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. Resolution is usually defined as the amount of resolvable detail in the horizontal and vertical directions in a picture. For example. This diagram shows that the vertical resolution is described as lines per inch (lpi) and the horizontal resolution is described as dots (pixels) per inch (dpi). A pixel is the smallest component in an image. Vertical resolution is the amount of resolvable detail in the vertical direction in a picture. The number of pixels per unit of area is called the resolution and more pixels per unit area provide more detail in the image. Each pixel can be characterized by the amount of intensity and color variations (depth) it can have.

the higher the frame rate. When the frame rate is too low. 30 fps for North American video.
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.2. This example shows that frame rates are the number of images that are sent over time (1 second). At the frame rate is reduced below approximately 24 frames per second (fps). 50 fps for European television and 60 fps for North American television.Chapter 3
Figure 3. 30 fps for North American video.3 shows the different types of frame rates and how lower frame rates can cause flicker in the viewing of moving pictures. Some of the common frame rates for moving pictures are 24 fps for film. Increasing the frame rate results in increased bandwidth requirements. 50 fps for European television and 60 fps for North American television. 25 fps for European video. Flicker typically happens when the frame rate is below 24 frames per second. The common frame rate formats are 24 fps for film. Video Resolution
In general. the better the quality of the video image. 25 fps for European video. flicker (fluctuations in the brightness of movie images) begins to occur. Figure 3. the images appear to flicker.

This diagram shows that wide screen television has an aspect ratio of 16:9 and that standard television and computer monitors have an aspect ratio of 4:3. The aspect ratio of the NTSC (analog television) standard is 4:3 for conventional monitors such as home television sets and 16:9 for HDTV (widescreen). Figure 3. Moving Picture Frame Rates
Aspect Ratio
Aspect ratio is the ratio of the number of items (such as pixels on a screen) as compared to their width and height.4 shows how aspect ratio is the relationship between width and height expressed as width:height.3. The aspect ratio determines the frame shape of an image.
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.IPTV Basics
Figure 3.

Chapter 3
Figure 3.
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. Aspect Ratio
Letterbox
Letterbox is the method of displaying wide screen images on a standard TV receiver where the wide screen aspect ratio is much larger than the standard television or computer monitor typical aspect ratio of 4:3. The result is part of the top and bottom areas of the screen area are blanked out (black) resulting in the formation of a box (a letterbox). Figure 3. This example shows that part of an image (of a boat) is lost on the left and right parts of the display.4.5 shows how the use of a letterbox allows an entire video image to be displayed on a screen that has an aspect ratio lower than the video image requires. This causes the display to appear within borders at the top and bottom of the image producing a horizontal box (the letterbox). Using a letterbox. the image size is reduced so its width can fit within the length of the screen area.

The process of drawing these lines on the screen is called scanning.IPTV Basics
Figure 3. the color (chrominance) and the audio. This scanning method is called interlacing. Each frame is divided into horizontal and vertical lines. To create a single frame picture on a television set. Each line is divided into pixels that are the smallest possible parts of the picture. This analog signal indicates the luminance and color information within the video signal.5. The frames are drawn to the screen in two separate scans. The video signal television picture into three parts: the picture brightness (luminance). the frame is drawn line by line. Sending a video picture involves the creation and transfer of a sequence of individual still pictures called frames. The number of pixels that can be displayed determines the resolution (quality) of the video signal.
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. The first scan draws half of the picture and the second scan draws in between the lines of the first scan. Letterbox
Analog Video
Analog video is the representation of a series of multiple images (video) through the use of a rapidly changing signal (analog).

The color component signals are added out of phase relative to each other. and SECAM. This example shows that an intensity only (black and white) signal is combined with color component signals. Figure 3. The Y intensity (brightness) component includes can be used as a black and white (monochrome) video. NTSC. Examples of composite video formats include Y. The color components are represented by the two signals U and V.6 shows how a composite video signal is combines video intensity (Y) and color signals (U and V) to produce a composite video signal.
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. The U and V are mixed with different phases (orthogonal) of a color carrier signal and combined to form a chrominance signal. U is the difference between Blue and Y (intensity) and V is the different between Red and Y. The Y component contains the synchronization signal (sync pulse) that coordinates the picture tube scanning (image creation) process. green. and synchronization information.
Composite Video
Composite video is a single electrical signal that contains luminance. Composite video signals are created by combining several analog signals. PAL. and blue (RGB). U and V. color. The combination of component video can produce any color and intensity of picture information.Chapter 3
Component Video
Component video consists of three separate primary color signals: red.

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.6. This allows the bandwidth of each component video part to be larger than for the signals combined in composite video and it eliminates the cross talk distortion that occurs when multiple signals are combined.
Interlacing
Field interlacing is the process used to create a single video frame by overlapping two pictures where one picture provides the odd lines and the other picture provides the even lines. S-video is a type of component video as the intensity and color components are sent as separate signals. Field interlacing is performed to reduce bandwdith and flicker. Composite Video
Separate Video (S-Video)
S-video is a set of electrical signals that represent luminance and color information.IPTV Basics
Figure 3. This offers the potential for S-video to have improved quality as compared to composite video.

3.4. Canada. the odd lines are displayed. Figure 3. The video source is broken into 30 frames per second and converted into multiple lines per frame. 2.
Figure 3. regardless of whether or not a color image is involved. every odd line (e. In frame one. In frame 3.Chapter 3
Figure 3. This process alternates very quickly so the viewer does not notice the interlacing operation. every even line (e.6.g. Each video line transmission begins with a burst pulse (called a sync pulse) that is followed by a signal that represents color and intensity.7 shows how the lines displayed on each frame are interlaced by alternating the selected lines between each image frame.5. etc) is displayed. In frame two. Field Interlacing
NTSC Video
NTSC video is an established standard for TV transmission that currently in use in the United States. Japan and other countries. Each line is sent until a frame is complete and the
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. 1.8 demonstrates the operation of the basic NTSC analog television system. The time relative to the starting sync is the position on the line from left to right. The abbreviation NTSC is often used to describe the analog television standard that transmits 60 fields/seconds (30 frames or pictures/second) and a picture composed of 525 horizontal scan lines. etc) is displayed.g.7.

IPTV Basics
next frame can begin. The television receiver decodes the video signal to position and control the intensity of an electronic beam that scans the phosphorus tube (“picture tube”) to recreate the display.
Figure 3. PAL is now used in many other parts of the world.8. The PAL system provides 625 lines of resolution (50 are blanking lines).
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. Analog NTSC Video
PAL Video
Phase alternating line video is a television system that was developed in the 1980’s to provide a common television standard in Europe. The PAL system uses 7 or 8 MHz wide radio channels.

Some of the common display formats include 4:2:2. and some Middle East countries. SIF.
4:2:2 Digital Video Format
4:2:2 digital video is a CCIR digital video format specification that defines the ratio of luminance sampling frequency as related to sampling frequencies for each color channel. the former Eastern Block countries. CIF and QCIF.
Digital Video
Digital video is a sequence of picture signals (frames) that are represented by binary data (bits) that describe a finite set of color and luminance levels. Figure 3. Because the human eye is more sensitive to light intensity than it is to color.9 shows the format of a 4:2:2 digital video on a display. a small portion of the video display has been expanded to show horizontal lines and vertical sample points of luminance (intensity) and
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. In this example.Chapter 3
SECAM Video
SECAM is an analog color TV system that provides 625 lines per frame and 50 fields per second. Sending a digital video picture involves the conversion of an image into digital information that is transferred to a digital video receiver. the former USSR. For every four luminance samples. Display formatting is the positioning and timing of graphic elements on a display area (such as on a television or computer display). This system is similar to PAL and is used in France. In order to transmit color the information is transmitted sequentially on alternate lines as a FM signal. there are two samples of each color channel. 4:2:0. The digital information contains characteristics of the video signal and the position of the image (bit location) that will be displayed. display formats can have more intensity components than color components.

In this example.10 the format of a 4:2:0 digital video on a display.
Figure 3.5 MHz and the sample frequency for color is 6. This example shows that the sample frequency for luminance for
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. This format has color samples (Cb and Cr) on every line that occur for every other luminance sample.9.75 MHz. Figure 3. there is one sample of each color channel that alternates on every other horizontal scan line. a small portion of the video display has been expanded to show horizontal lines and vertical sample points of luminance (intensity) and chrominance (color). 4:2:2 Digital Video Format
4:2:0 Digital Video Format
4:2:0 digital video is a CCIR digital video format specification that defines the ratio of luminance sampling frequency as it is related to sampling frequencies for each color channel. is 13.IPTV Basics
chrominance (color). For every four luminance samples. This example shows that the sample frequency for luminance for 4:2:2.

This example shows that the sample frequency for luminance for SIF
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. is 13.11 the format of a SIF digital video on a display. SIF has a luminance resolution of 360 x 288 (625 lines) or 360 x 240 (525 lines) and a chrominance resolution of 180 x 144 (625 lines) or 180 x 120 (525 lines).10.5 MHz and the sample frequency for color is 6. Figure 3.75 MHz. a portion of the video display 8 x 8 has been expanded to show horizontal lines and vertical sample points of luminance (intensity) and chrominance (color). In this example.Chapter 3
4:2:0. This format has color samples (Cb and Cr) on every other line and that the color samples occur for every other luminance sample.
Figure 3. 4:2:0 Digital Video Format
Source Intermediate Format (SIF)
Source intermediate format is a digital video format having approximately 1/2 the resolution of analog television (PAL/NTSC).

261 and H. CIF coding includes interframe prediction (using key frames and difference frames).11.75 MHz and the sample frequency for color is 3.
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.IPTV Basics
is 6.264 compression standards.
Figure 3. mathematical transform coding and motion compensation. SIF Digital Video Format
Common Intermediate Format (CIF)
Common interchange format (CIF) is an image resolution format that is 360 pixels across by 248 pixels high (360x248).375 MHz. The CIF standard is defined in the ITU H. This example shows that the color samples occur on every 4th line and that the color samples occur for every other luminance sample.

Video Digitization
Video digitization is the conversion of video component signals or composite signal into digital form through the use of an analog-to-digital (pronounced A to D) converter. it is identified by the letter p at the end of the frame rate (e. When video is stored in progressive form. the image is filtered into red. Each of the resulting
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. The QCIF standard was developed in 1990 is defined by the ITU in as H. analog video) or from film.264 compression standards.261 and H. The A/D converter periodically senses (samples) the level of the analog signal and creates a binary number or series of digital pulses that represent the level of the optical image. Digital video may be created from another video format (e. 60p is 60 images per second and each frame is unique).12 shows a fundamental process that can be used to digitize moving pictures or analog video into digital video. Digital video is usually stored in progressive format where each image in a sequence of a movie adds a new image (as opposed to a partial interlaced image) progression in a moving picture.
Video Capturing
Video capturing is the process of receiving and storing video images. Video capture typically refers to capture of video images into digital form.g. mathematical transform coding and motion compensation.g. For color images. H. green and blue component colors.261 coding includes interframe prediction (using key frames and difference frames). Figure 3.Chapter 3
Quarter Common Intermediate Format (QCIF)
Quarter common interchange format (QCIF) is an image resolution format that is 180 pixels across by 144 pixels high (180x144).

12. Deinterlacing is the process of converting interlaced images into a form that of unique sequential images.IPTV Basics
images is scanned in lines from top to bottom to convert the optical level to an equivalent electrical level.
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. The electrical signal level is periodically sampled and converted to its digital equivalent level. This example shows that analog signals can have 256 levels (0-255) and that this can be represented by 8 bits of information (a byte). Analog video is converted into a progressive form by deinterlacing. Video Digitization
Analog video is typically stored and transmitted in interlaced format where a single frame is converted into two interlaced fields.
Figure 3.

repeating the next film frame image 2 times and repeating this process 3 repeats and 2 repeats to create 60 images (fields) per second.13. movie) images and converting it into a sequence of video images. each frame image
Figure 3. Because the frame rate of film is different than video. Pulldown
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. The 3:2 process operates by repeating a film frame image 3 times.Chapter 3
Film to Video Conversion
Film to video conversion is the process of scanning film (e. 3:2 pulldown is sometimes called Telecine because Telecine was a machine that performed the pulldown conversion. To create the 60 frames per second.g. Figure 3. the frame rate is adapted through the use of a pulldown process.13 shows how 24 frame per second (fps) film is converted to 60 field per second (fps) video. 3:2 pulldown is a process of converting film that operates at 24 frames per second to video at 60 fields per second.

IPTV Basics
must be copied (repeated) 2. you don’t get exactly the same image that you started with despite the fact JPEG was specifically designed to discard information not easily detected by the human eye.25 bits per pixel for fair quality to 2. When compressed.
Video Compression
Video compression is the process of reducing the amount of transmission bandwidth or the data transmission rate by analog processing and/or digital coding techniques. The JPEG committee has produced an image compression standard format that is able to reduce the bit per pixel ratio to approximately 0. This example shows that frames with in the film are used to create 2 or 3 interlaced video fields. image or section of information. JPEG is a working committee under the auspices of the International Standards Organization (ISO) with the goal of defining a standard for digital compression and decompression of still images for use in computer systems. One of the common forms of spatial compression is specified by the joint picture experts group (JPEG). The JPEG committee has defined a set of compression methods that are used to provide for high-quality images at varying levels of compression up
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.
Spatial Compression (Image Compression)
Spatial compression is the analysis and compression of information or data within a single frame. JPEG uses lossy compression methods that result in some loss of the original data.5 bits per pixel for high quality. Moving pictures can be compressed by removing redundancy within each image (spatial redundancy) or between successive images over a period of time (temporal redundancy).5 times. When you decompress the original image. a video signal can be transmitted on circuits with relatively narrow channel bandwidth or using data rates 50 to 200 times lower than their original uncompressed form.

14. The new block of coefficients is converted to a sequence of data (serial format) by a zig-zag process. This is because the compression methods tend to approximate portions of the image and the approximation of lines or sharp boundaries tends to get blurry with unwanted artifacts. The data
Figure 3. This diagram shows that JPEG compression takes a portion (block) of a digital image (lines and column sample points) and analyzes the block of digital information into a new block sequence of frequency components (DCT). JPEG Image Compression
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. the coefficient levels can be changed a small amount (lossy compression) without significant image differences (thresholding). JPEG compression typically works better for photographs and reference video frames (I frames) rather than line art of cartoon graphics. Optionally. The JPEG compression system can use compression that is fully reversible (no loss of information) or that is lossy (reversible with some loss of quality). The sum of these DCT coefficient components can be processed and added together to reproduce the original block.Chapter 3
to approximately 50:1. Lossy compression does not have the ability to guarantee the exact recreation of the original signal when it is expanded back from its compressed form. Lossy compression is a process of reducing an amount of information (usually in digital form) by converting it into another format that represents the initial form of information. Figure 3.14 shows the basic process that can be used for JPEG image compression.

images or sections of information. In each
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. Motion estimation is a computer-intensive process that is used to achieve high compression ratios. MPEG is a working committee that defines and develops industry standards for digital video systems. The process involves an exhaustive search for many blocks surrounding the current block from the previous frame. Figure 3. Temporal video compression involves analyzing the changes that occur between successive images in a video sequence that that only the difference between the images is sent instead of all of the information in each image. time compression can use motion estimation.g. These standards specify the data compression and decompression processes and how they are delivered on digital broadcast systems.IPTV Basics
is then further compressed using run length coding (RLC) to reduce repetitive bit patterns and then using variable length coding (VLC) to convert and reduce highly repetitive data sequences. MPEG is part of International Standards Organization (ISO). Motion estimation is the process of searching a fixed region of a previous frame of video to find a matching block of pixels of the same size under consideration in the current frame.
Time Compression (Temporal Compression)
Temporal compression is the analysis and compression of information or data over a sequence of frames. digital video). Block matching is the process of matching the images in a block (a portion of an image) to locations in other frames of a digital picture sequence (e. One of the more common forms of temporal compression used for digital is specified by the Motion Picture Experts Group (MPEG). This diagram shows that a bird in a picture is flying across the picture.15 shows how a digital video system can use motion estimation to identify objects and how their positions change in a series of pictures. To accomplish this.

the motion estimation system looks for blocks that approximate other blocks in previous pictures. Data compression is a technique for encoding information so that fewer data bits of information are required to represent a given amount of data. Run length encoding is a method of compressing digital information by representing repetitive data information by a notation that indicates the data that will be repeated and how many times the data will be repeated (run length). Using data compression can reduce coding redundancy. Motion Estimation
picture frame. Over time.15.
Coding Redundancy (Data Compression)
Coding redundancy is the repetition of information or bits of data within a sequence of data. the digital video motion estimation system finds matches and determines the paths (motion vectors) that these objects take.Chapter 3
Figure 3. Some of the common forms of data compression used in video compression include run length encoding (RLE) and variable length encoding (VLE).
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.

16.16 shows how video compression may use spatial and temporal compression to reduce the amount of data to represent a video sequence. Figure 3. Video Compression
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.IPTV Basics
Variable length encoding is a method of compressing digital information by representing repetitive groups of data information by code that are used to look up the data sequence along with how many times the data will be repeated (variable length). The first frame of this example shows that a picture of a bird that is flying in the sky can be compressed by separating the bird image from the
Figure 3. This diagram shows that a frame in a video sequence may use spatial compression by representing the graphic elements within the frame by objects or codes.

The more pixels per unit area provide more detail in the image.Chapter 3
blue background and making the bird an object and representing the blue background as a box (spatial compression). The different types of frames can be combined into a group of pictures. Pixels can range in size and shape and are composed of color (possibly only black on white paper) and intensity. For the MPEG system. Slices make up frames. Video images are composed of pixels.
Blocks
Blocks are portions of an image within a frame of video usually defined by a number of horizontal and vertical pixels. a frame is divided into 16 by 16 pixel sized macroblocks. Typically. which come in several different types. Macroblocks can be combined into slices and each image may contain several slices. each block is composed of 8 by 8 pixels and each block is processed separately.
Pixels
A pixel is the smallest component in an image. The next sequence of images only needs to move the bird on the background (temporal compression).
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. The number of pixels per unit of area is called the resolution.
Macroblocks
A macroblock is a region of a picture in a digital picture sequence (motion pictures) that may be used to determine motion compensation from a reference frame to other pictures in a sequence of images. which is also groupings of four 8 by 8-pixel blocks. MPEG system groups pixels within each image into small blocks and these blocks are grouped into macroblocks.

Intra Frames (I-Frames) Intra frames (I-Frames) are complete images (pictures) within a sequence of images (such as in a video sequence). To compress video signals. predicted frames that are based on previous reference frames (P-frames). This means that I-frames require more data than compressed frames. the MPEG system categorizes video images (frames) into different formats. bidirectionally predicted frames using preceding frames and frames that follow (B-Frames). In an interlaced scanning video system.
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. These formats vary from fame types that only use spatial compression (independently compressed) to frames that use both spatial compression and temporal compression (predicted frames). The only redundancy that can be removed from I frames is spatial redundancy. Slices can vary in size and shape. a frame comprises two fields. I-frames are used as a reference for other compressed image frames and I frames are completely independent of other frames. MPEG system frame types include independent reference frames (I-frames). the first field typically containing the odd numbered scan lines and the second field typically containing the even numbered scan lines. Each field contains half of the video scan lines that make up the picture.
Frames
A frame is a single still image within the sequence of images that comprise the video.IPTV Basics
Slice
A slice is a part of an image that is used in digital video and it is composed of a contiguous group of macroblocks. and DC frames (basic block reference levels).

For all frames within a
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. Because B-frames must be compared to two other frames. Bframes require the use of frames that both precede and follow the B-frames. fast forwarding) and are not used in other versions of MPEG. Because image components are often repeated within a sequence of images (temporal redundancy).
Groups of Pictures (GOP)
Frames can be grouped into sequences called a group of pictures (GOP). Bi-Directional Frames (B-Frames) Bi-directional frames (B-Frames) are images (pictures) within a sequence of images (such as in a video sequence) that are created using information from preceding images and images that follow (such as from I-Frames and predicted frames P-Frames). the amount of image processing that is required for B-frames (e. Because B-Frames are created using both preceding images and images that follow. D frames are used in the MPEG-1 system to allow rapid viewing (e. B-frames offer more data compression capability than P-Frames.g. motion estimation) is typically higher than P frames.Chapter 3
Predicted Frames (P-Frames) Predicted frames (P-Frames) are images (pictures) within a sequence of images (such as in a video sequence) that are created using information from other images (such as from I-Frames). the use of P-Frames provides substantial reduction in the number of bits that are used to represent a digital video sequence (temporal data compression). DC Frames (D-Frames) A DC frame is an image in a motion video sequence that represents the DC level of the image. A GOP is an encoding of a sequence of frames that contain all the information that can be completely decoded within that GOP.g.

M is the distance between successive P-Frames and N is the distance between successive I-Frames. MPEG Group of Pictures (GOP)
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. Typical values for MPEG GOP are M equals 3 and N equals 12. This example shows that a GOP starts within an intra-frame (I-frame) and that intraframes typically require the largest number of bytes to represent the image (200 kB in this example).17. the frames so referenced (I-frames and P-frames) are also included within that same GOP. The depth m represents the number of frames that exist between the I-frames and P-frames. The temporal distance of images is the time or number of images between specific types of images in a digital video.
Figure 3.IPTV Basics
GOP that reference other frames (such as B-frames and P-frames). A GOP can be characterized as the depth of compressed predicted frames (m) as compared to the total number of frames (n). The types of frames and their location within a GOP can be defined in time (temporal) sequence. Figure 3.17 shows how different types of frames can compose a group of pictures (GOP).

Figure 3. To overcome the challenge of error propagation. A closed group of pictures is a sequence of image frames can successfully decode all the frames within its sequence without using information from other GOPs.Chapter 3
Groups of pictures can be independent (closed) GOP or they can be relative (open) to other GOPs. the error may propagate through additional frames (error retention). when errors occur on previous frames. Because P and B frames are created using other frames.18 shows how errors that occur in an MPEG image may be retained in frames that follow. MPEG Error Retention
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. An open group of pictures is a sequence of image frames that requires information from other GOPs to successfully decode all the frames within its sequence. I frames are sent periodically to refresh the images and remove and existing error blocks. Figure 3.18. This example shows how errors in a B-Frame are transferred to frames that follow as the B-Frame images are created from preceding images.

Spatial scalability is the ability of a media file or picture image to reduce or vary the number of image components or data elements representing a picture over a given area (spatial area) without significantly changing the quality or resolution of the image.IPTV Basics
Compression Scalability
Compression scalability is the ability of a media compression system to adapt its compression parameters for various conditions such as display size (spatial scalability). Temporal scalability is the ability of a streaming media program or moving picture file to reduce or vary the number of images or data elements representing that media file for a particular time period (temporal segment) without significantly changing the quality or resolution of the media over time. An enhancement layer is a stream or source of media information that is used to improve (enhance) the resolution or appearance of underlying image (e. Layered compression starts with the use of a base layer may be decoded separately to provide a low resolution preview of the image or video and to reduce the decoding processing requirements (reduced complexity). Layered scalability is the use of multiple layers in an image that can be combined to produce higher resolution images or video.264)
Advanced video coding is a video codec that can be used in the MPEG-4 standard.g. base layers). changing the frame rate (temporal scalability) or quality of signal (signal to noise scalability). combining multiple transmission channels (layered scalability). The AVC coder provides standard definition (SD) quality at approximately 2 Mbps and high definition (HD) quality at approximately 6-8 Mbps. Signal to noise ratio scalability is the ability of a media file or picture image to reduce or vary the number of image components or data elements representing that that picture to compensate for changes in the signal to noise ratio of the transport signal.
Advanced Video Coding (AVC/H.
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.

Animated Objects Animated objects are graphic elements that can be created and changed over a period of time. Object Coding Object coding is the representation of objects (such as a graphic item in a frame of video) through the use of a code or character sequence. Audiovisual objects are parts of media images (media elements). Media elements are component parts of media images or content programs.Chapter 3
The AVC coding system achieves higher compression ratios by better analysis and compression of the underlying media. Media images or moving pictures may be analyzed and divided into audiovisual objects to allow for improved media compression or audiovisual objects may be combined to form new images or media programs (synthetic video). it can create or represent objects in synthetic form (animated objects) and it can use variable block sizes to more efficiently represent (deblock) images with varying edges. Background sprites usually don’t change or they change relatively slowly. Animated objects can be used to create synthetic video (e. texture and size. This allows the MPEG
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. A background sprite is a graphic object that is located behind foreground objects. The AVC system can identify and separately code objects from video sequences (object coding). A media element is considered a unique specific element such as a shape. moving picture information that is created through the use creating image components by non-photographic means).g. The types of objects that can be used in AVC system range from static background images (sprites) to synthetic video (animation). MPEG-4 uses an efficient form (a binary form) of virtual reality modeling language (VRML) to create 3 dimensional images. A media element can be the smallest common denominator of an image or media program component.

The use of variable block sizes allows for using smaller blocks in portions of graphic images that have lots of rapid variations (such as the edge of a sharp curve). File download commonly refers to retrieving files from a web site server to another computer.
File Downloading
File download is the transfer of a program or of data from computer server to another computer. transferred as the video is played (streaming) or played as soon as enough of the media has been transferred (progressive downloading). IP video can be downloaded completely before playing (file downloading). Figure 3. Also.
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.
IP Video Transmission
IP video transmission is the transport of video (multiple images) that is in the form of data packets to a receiver through an IP data network. it allows larger blocks in areas that have a limited amount of variation (such as the solid blue portion of the sky). This diagram shows how the web server must transfer the entire media file to the media player before viewing can begin.19 shows how to download movies through the Internet.IPTV Basics
system to send a mathematical model of objects along with their associated textures instead of sending detailed images that require large data transmission bandwidths. Variable Block Sizes Variable block sizes are groups of image bits that make up a portion of an image that vary in width and height.

20 shows how to stream movies through the IP data networks. a video media server system will deliver a stream of video and audio (both can be compressed) to a client. Upon request. This diagram shows that streaming allows the media player to start displaying the video before the entire contents of the file have been transferred. Digital Video File Downloading
Video Streaming
Video streaming is the process of delivering video. Video streaming can be transmitted with or without flow control. When a video streaming session can obtain and use feedback from the receiver. Figure 3. The client will receive the data stream and (after a short buffering delay) decode the video and audio and play them in synchronization to a user. transmission or media application playing capabilities. Intelligent streaming is the providing of a continuous stream of information such as audio and video content with the ability to dynamically change the characteristics of the streaming media to compensate for changes in the signal source. usually along with synchronized accompanying audio in real time (no delays) or near real time (very short delays).Chapter 3
Figure 3. This diagram also shows that the streaming process usually has some form of
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. it is called intelligent streaming.19.

Video Streaming
Rate Shaping Rate shaping is the identification.g. This allows the media server to take action (such as increase or decrease compression and data transmission rate) if the connection is degraded or improved. stream thinning may be used.IPTV Basics
feedback that allows the viewer to control the streaming session and to provide feedback to the media server about the quality of the connection. Stream thinning is the process of removing some of the information in a media stream (such as removing image
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. rate shaping may be used to adjust the bandwidth that is assigned to a streaming connection service. high cost connection).20. If the bandwidth available for a streaming media session is limited or it is decided to reduce or adjust the bandwidth for other reasons (e.
Figure 3. When the bandwidth available for the streaming session becomes more limited. categorization and prioritization of the transfer of data or information through a system or a network to match user requirements with network capacity and service capabilities.

HTTP streaming manages the sequential transferring of media files through an IP data network (such as the Internet) using HTTP commands.
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.
Tiling
Tiling is the changing of a digital video image into square tiles that are located in positions other than their original positions on the screen. jerkiness.Chapter 3
frames) to reduce the data transmission rate. Digital video and transmission system impairments include tiling.
Digital Video Quality (DVQ)
Digital video quality is the ability of a display or video transfer system to recreate the key characteristics of an original digital video signal. Frame dropping may be used to temporarily reduce the data transmission speed or to reduce the video and image processing requirements. error blocks. An example of progressive downloading is HTTP streaming.
Progressive Downloading
Progressive downloading is transferring of a file or data in a sequential process that allows for the using of portions of the data before the transfer is complete. Frame Dropping Frame dropping is the process of discarding or not using all the video frames in a sequence of frames. artifacts (edge busyness) and object retention. Stream thinning may be used to reduce the quality of a media stream as an alternative to disconnecting the communication session due to bandwidth limitations.

21 shows an example of how error blocks are displayed on a digital video signal.IPTV Basics
Error Blocks
Error blocks are groups of image bits (a block of pixels) in a digital video signal that do not represent error signals rather than the original image bits that were supposed to be in that image block. the error blocks continue to display until a new image that is received does not contain the errors. Jerkiness may occur when a significant number of burst errors occur during transmission that results in the inability of a receiver to display a
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.21. In this example. Digital Video Error Blocks
Jerkiness
Jerkiness is holding or skipping of video image frames or fields in a digital video. This diagram shows that transmission errors result in the loss of picture blocks.
F Figure 3. Figure 3.

In the processing or transmission of audio or video signals. Mosquito noise is a blurring effect that occurs around the edges of image shapes that have a high contrast ratio. a distortion or modification produced due to the actions of people or due to a process designed by people.Chapter 3
new image frame. in general. Mosquito Noise Artifacts <
Object Retention
Object retention is the keeping of a portion of a frame or field on a digital video display when the image has changed. Instead. are results. This diagram shows that the use of lossy compression on images that have sharp edges (such as text) can generate blurry images.22.
Artifacts
Artifacts. Object retention occurs when the data stream that represents the object becomes unusable the digital
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.22 shows an example of mosquito noise artifacts.
Figure 3. Mosquito noise can be created through the use of lossy compression when it is applied to objects that have sharp edges (such as text). effects or modifications of the natural environment produced by people. Figure 3. the digital video receiver may display the previous frame to minimize the perceived distortion (s jittery image is better than no image).

The digital video receiver decides to keep displaying the existing object in successive frames until an error free frame can be received.23.IPTV Basics
video receiver.
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. processes and procedures that are used for delivering and controlling the real-time delivery of media (such as audio and or video streaming). some of the bits from image objects are received in error. This example shows that an original sequence where the images have been converted into objects. Streaming control protocols control the setup. recording and tear down of streaming sessions. which results in the objects remaining (a bird and the sail of a boat) in the next few images until an error free portion of the image is received.23 shows a how a compressed digital video signal may have objects retained when errors occur. playing. Figure 3. Digital Video Object Retention
Streaming Control Protocols
Streaming protocols are commands. When the scene change occurs.
Figure 3. pausing. Streaming control protocols that are used for IPTV systems include real time streaming protocol (RTSP) and digital storage media command and control (DSM-CC).

fast forward) via bi-directional (two-way) communication sessions. Motion JPEG (MJPEG) and Windows Media (VC-1). The MPEG standards specify the data compression and decompression processes and how they are delivered on digital broadcast systems.
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. DSM-CC provides VCR type features. digital audio and digital video) along with descriptive information (meta tags). RTSP is defined in RFC 2326.g.
Digital Storage Media Command and Control (DSM-CC)
Digital storage media command and control is an MPEG extension that allows for the control of MPEG streaming.
Video Formats
Video formatting is the method that is used to contain or assign digital media within a file structure or media stream (data flow). stopping. Video formats can be a raw media file that is a collection of data (bits) that represents a flow of image information or it can be a container format that is a collection of data or media segments in one data file. media position control (e.g. A file container may hold the raw data files (e. Some of the common video formats used in IPTV system include MPEG. Real media. Quicktime.
MPEG
Motion picture experts group develops digital video encoding standards. Video formats are usually associated with specific standards like MPEG video format or software vendors like Quicktime MOV format or Windows Media WMA format. RTSP provides the control of playing.Chapter 3
Real Time Streaming Protocol (RTSP)
Real time streaming protocol is an Internet protocol that is used for continuous (streaming) audio and video sessions.

rm file extension.
Quicktime
Quicktime is a computer video format (sound.
Real Media
Real Media is a container format developed by the company “Real” and is used for streaming media files. Real Media files are usually designated by the . QuickTime files are designated by the . MPEG has several compression standards including MPEG-1. MPEG-1 was designed for slow speed stored media with moderate computer processing capabilities.
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. MPEG-1 offers less than standard television resolution. synchronized and converted (rendered) back into a multimedia format. The MPEG-4 specification was designed for allows for television transmission over packet data networks such as broadband Internet.IPTV Basics
The MPEG system defines the components (such as a media stream or channel) of a multimedia signal (such as a digital television channel) and how these channels are combined. MPEG-2 is designed and used for television broadcaster (radio. MPEG-4 (original) and MPEG-4 AVC/H. transmitted. graphics and movies) that was developed by Apple computer in the early 1990s.mov extension.264. MPEG-2. The initial release of the MPEG-4 system has the same amount of video compression as MPEG2.264 which increased the compression amount which added significant benefit to companies installing MPEG systems (more channels in less bandwidth). received. Real Media files can use several types of coding processes. separated. satellite and cable TV) of standard and high definition television. The MPEG-4 system was enhanced with a 2nd type of compression called
advanced video coding (AVC)/H.

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. The .Chapter 3
Motion JPEG (MJPEG)
A motion JPEG is a digital video format that is only composed of independent key frames. VC-1 is the designation for Microsoft’s Windows Media Player codec by the SMPTE organization. Because MJPEG does not use temporal compression. each video frame can be independently processed without referencing other frames.WM file contains a header (beginning portion) that describes the types of media. their location and their characteristics that are contained within the media file.
Windows Media (VC-1)
Windows media .WM is a container file format that holds multiple types of media formats.

IPTV Basics
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coding. decoding and converting (rendering) IP audio data into its original audio form. addressing. decodes the data and converts the digital audio back into its original video form. codes and/or compresses the data.
Figure 4. transfers the packets through a packet data network.1 shows how audio can be sent via an IP transmission system. This diagram shows that an IP audio system digitizes and reformats the original audio. Figure 4. transferring.1. receiving. recombines the packets and extracts the digitized audio. IP Audio System
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.Chapter 4
Introduction to IP Audio
IP audio is the transfer of audio (sound) information in IP packet data format. Transmission of IP audio involves digitizing audio. adds IP address information to each packet.

There are many variations of surround sound ranging from 3 speakers to more than 12 speakers. However. Stereo signals may be transmitted through the use of independent channels or it may be sent by sending a single (mono) channel along with channel difference signal(s) that can be combined with the mono source to produce the two separate channels. Generally speaking. a loss of fidelity (distortion) typically occurs as a result of the inability of the multiple channels to produce a signal that represents a single wavefront. 100
. The use of stereo can add the ability to hear audio where the relative position of sound sources (such as instruments in a band) can be determined. For example. surround sound 5.1 consists of 5 full audio channels and 1 low frequency channel. Use of a single communication channel to send stereo can reduce the bandwidth requirements.
Surround Sound
Surround sound is the reproduction of audio that surrounds the listener with sound that is provided from multiple speaker locations. The use of surround sound can allow a listener to determine the relative position of sound sources around them (such as in front and behind).IPTV Basics
Monoral (Mono)
Monoral audio is the generation and reproduction of sound in a single channel of audio. when mono signals are created from multiple channels. surround sound configurations are identified by the number of full audio channels plus the number of low frequency channels. Monoral signals can be created from multichannel signals (such as from stereo) by combining multiple channels. Monoral signals are produced by a microphone that is located in a single point near the audio source that captures a sample of the audio wavefront at that location.
Sterophonic (Stereo)
Stereo is the generation and reproduction of a 2-channel sound source (left and right).

Surround Sound
Analog Audio
Analog audio is the representation of a series of multiple sounds through the use of a signal that can continuously change (analog).2 shows how surround sound uses multiple speaker sources to create the effects of audio that surrounds the listener. This diagram shows a surround sound system that contains 6 channels – front left.2.
Figure 4.
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Figure 4. Audio signals are transmitted through air by sound pressure waves and through wires by electrical signals. rear right. Sound pressure waves are converted to electrical signals by a microphone. This analog signal indicates the level and frequency information within the audio signal. front right. rear left. center and a low frequency enhancement (sub-audio) speaker.

as the sound pressure from a person’s voice is detected by a microphone.
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. pre-emphasis/de-emphasis.IPTV Basics
Figure 4. or energy) as time progresses. loudness. companding/expanding and other noise reduction modifications. it is converted to its equivalent electrical signal.3 shows a sample analog signal created by sound pressure waves. The difference between the minimum and maximum frequency analog signals is called the frequency range and the difference between minimum and maximum signal levels that an analog signal can have its dynamic range.
Figure 4.3. Analog signals may be processed through the use of filtering. In this example. Analog Audio
Sound signals start in analog (continuous variation) form. The dynamic range is typically expressed in decibels against a reference level. This diagram shows that analog audio signals continuously vary in amplitude (height.

g. In this example. These signals may be multiple channels (frequency multiplexing) or may be signals that are used for control purposes. Filters may remove (band-reject) or allow (band-pass) portions of analog (possibly audio signals) that contain a range of high and low frequencies that are not necessary to transmit. the audio signal is processed through a filter to remove very high and very low frequency parts (audio band-pass filter). In some cases. the control signal is usually removed from the receiver by a filter.4 shows typical signal processing for an audio filter. Audio Signal Filtering
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. These unwanted frequency parts are possibly noise and other out of audio frequency signals that
Figure 4. the filtering of specific frequencies can alter the shape of the analog signal. Because analog signals (electrical or optical) are actually constructed of many signals that have different frequencies and levels. Figure 4. a supervisory tone that is used to confirm a connection exists). If the signal that is added is used for control purposes (e. additional signals (at different frequencies) may be combined with audio or other carrier signals prior to their transmission.4.Chapter 4
Audio Filtering
Analog signal filtering is a process that changes the shape of the analog signal by restricting portions of the frequency bandwidth that the signal occupies.

After an audio signal is processed by the audio band-pass filter.5 shows the basic signal emphasis and de-emphasis process. The relative balance of high-frequency and lowfrequency components is restored in a receiver by de-emphasis. De-emphasis is the alteration (decreasing) of the characteristics (e. This emphasizes the higher frequency
Figure 4. This diagram shows that the amount of amplifier gain is increased as the frequency of input signal is increased.g.
Pre-Emphasis and De-Emphasis
Pre-emphasis is the increase in the amplitude of the high-frequency components in a transmitted signal that is used to overcome noise and attenuation in the transmission system.IPTV Basics
could distort the desired signal. Pre-Emphasis and De-Emphasis
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. Figure 4.5. The high frequencies can be seen as rapid changes in the audio signal. the sharp edges of the audio signal (high frequency components) are removed. amplitude) of a signal in proportion to another characteristic (such as frequency).

This keeps the input level to the modulator to a relatively small dynamic range. Of course.. an expanding system is used to provide additional amplification to the upper end of the output signal. a de-emphasis system is used to reduce additional amplification to the upper frequency parts of the output signal. This recreates the shape of the original input audio signal.g. softer talker). The use of companding allows the level of audio signal that enters the modulator to have a smaller overall range (higher minimum and lower maximum) regardless if some people talk softly or boldly. the process of companding must be reversed at the receiving end (called expanding) to recreate the original audio signal. As a result of companding. Figure 4. At the receiving end of the system. This can create distortion so companding allows the modulator to convert the information signal (audio signal) with less distortion.
Companding and Expanding
Companding is a system that reduces the amount of amplification (gain) of an audio signal for larger input signals (e.6 shows the basic signal companding and expanding process.Chapter 4
components as they are applied to the modulator. high-level signals and low-level signals input to a modulator that may have a different conversion level (ratio of modulation compared to input signal level). louder talker).. This diagram shows that the amount of amplifier gain is reduced as the level of input signal is increased. Expanding increases the amount of amplification (gain) of an audio signal for smaller input signals (e. At the receiving end of the system. This recreates the shape of the original input audio signal.
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.g.

Dolby SR and Digital Dolby.1) is an audio compression and channel multiplexing format that allows for the transmission of up to 6 channels (5 audio and 1 sub-audio).
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. Digital Dolby® Digital Dolby (also known as Dolby 5.IPTV Basics
Figure 4. The original Dolby noise reduction process that was developed in 1960s used companding and expanding to adjust the dynamic range of the audio into a range that was more suitable for stored or transmitted medium. Dolby S. Since its original development.6. Dolby B. Dolby C. The sub-audio channel produces lower sound frequencies and is called the low frequency enhancement (LFE) channel. Companding and Expanding Audio
Dolby® Noise Reduction (Dolby NR)
Dolby is an audio signal processing system that is used to reduce the noise or hiss that was invented by Ray Dolby. various enhancements to the Dolby system have been developed including Dolby A.

right and center) and a subwoofer channel.
Digital Theater Sound (DTS) Digital theater sound is a surround sound system that uses up to six digital audio channels.
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. Dolby Pro Logic®
Dolby Pro Logic is a surround sound system that adds an additional audio channel for central speaker located in the front. processing. Dolby Surround® Dolby Surround is a version of Dolby Stereo that is used in home entertainment systems. The codes are located along each frame produce a pattern that matches codes that are stored on the CD and these codes are matched to ensure the movie and the audio are correctly synchronized. The use of digital audio allows for more simple storage. right speaker and a rear speaker. and transmission of audio signals. Dolby Surround can produce similar sound effects as the Dolby Stereo system that is used in theater using a left speaker. The DTS system includes three front sound channels (left. The DTS system also has separate channels for the left and right side of the theater. The DTS system uses a CD audio disk that is synchronized with the movie time codes that are stored on the film.Chapter 4
Dolby AC-3® Dolby AC-3 is a digital compression process that was developed by Dolby® laboratories that is commonly used in movie theaters and on DVDs.
Digital Audio
Digital audio is the representation of audio information in digital (discrete level) formats.

Analog signals are commonly sampled at the Nyquist rate or above.000 samples per second (for music quality). The sampling rate must be fast enough to capture the most rapid changing rates (highest frequency) contained within the analog signal. The A/D converter periodically senses (samples) the level of the analog signal and creates a binary number or series of digital pulses that represent the level of the signal. the analog signal is digitized by using an analog-to-digital (pronounced A to D) converter. the value of the next sequential bit is 2 times larger. or any combination of these functions. The typical sampling rate for conversion of analog audio ranges from 8. Sampling Rate Sampling rate is the rate at which signals in an individual channel are sampled for subsequent modulation. To convert analog audio signals to digital form. The sampling frequency is usually specified as the number of samples per unit time. this frequency is twice the rate of the highest frequency contained in the signal being sampled. In the binary system.IPTV Basics
Audio Digitization
Audio digitization is the conversion of analog audio signal into digital form. Audio digitization converts specific voltage levels into digital bytes of information which are based on the value (weighting) of the binary bit position. Normally. coding.
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. The Nyquist rate is the lowest sampling frequency that can be used for analog-to-digital conversion of a signal without resulting in significant aliasing (false signal characterizations). Sampling is the process of taking samples of an electronic signal at equal time intervals to typically convert the level into digital information.000 samples per second (for telephone quality) to 44. quantization.

This conversion process results in quantization noise.g.7 shows how the audio digitization process can be divided into sampling rate and quantization level.Chapter 4
Bit Depth Bit depth is the number of bits that are used to represent the sample levels in an audio recording. Digital companding assigns weights to bits within a byte of information that is different than the binary system. Figure 4. This diagram shows that the quantization level may not be exactly the same value of the actual sample level. Because a quantization number is a value that cannot represent every possible signal level. louder talker). This companding process increases the dynamic range of a binary signal by assigning different weighted values to each bit of information than is defined by the binary system. Quantization noise is reduced by increasing the number of samples or the number of bits that represent each sample. smaller bits are given larger values that than their binary equivalent. quantization of a signal results in selecting a value closest to that actual sample level. Bit depth is determined by the number of quantization levels. Quantization level is the number that represents the value of a sampled signal. the more accurate the information can be represented providing for increased quality. The closest quantization level is used and this causes quantization distortion. Digital Companding Digital audio systems may use digital companding to reduce the amount of amplification (gain) of a digital audio signal for larger input signals (e. The larger the number of bits.
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. The companding process increases the dynamic range of a digital signal that represents an analog signal.. This diagram shows that an analog signal that is sampled at periodic time intervals and that the each sample gets a quantization level. This skewing of weighting values gives better dynamic range. Quantization noise (or distortion) is the error that results from the conversion of a continuous analog signal into a finite number of digital samples that can not accurately reflect every possible analog signal level.

A dither signal commonly consists of white noise signal. a converter is used to translate the different coding levels. the digitization of an audio signal would produce a very small square wave signals.
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. Without a dither signal. Audio Sampling and Quantization
Two common encoding laws are u-Law and A-Law encoding. When different types of encoding systems are used.7. u-Law encoding is primarily used in the Americas and A-Law encoding is used in the rest of the world.IPTV Basics
Figure 4. Dither Dither is a random signal that is added to an analog signal during the digital audio conversion process to reduce or mask the effects of quantization noise that occurs at low levels.

Compression ratio is a comparison of data that has been compressed to the total amount of data before compression.Chapter 4
Audio Format Conversion
Audio conversion is the process of changing audio signals from one format to another format. a file compressed to
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. Audio compression coders and decoders (codecs) analyze digital audio signals to remove signal redundancies and sounds that cannot be heard by humans. It is possible to highly compress digital audio by removing sounds that can be heard or perceived by listeners through the process of perceptual coding.g. Digital audio data is random in nature. Key types of audio coding include waveform coding. This means that audio signals do not have a high amount of redundancy. unlike digital video. which has repetitive information that occurs on adjacent image frames. store or transfer audio signals. speech audio as compared to music). The type of coder (type of analysis and compression) can dramatically vary and different types of coders may perform better for different types of audio sounds (e. However. For example. it is called transcoding. The human ear can hear sounds from very low frequencies (20 Hz) to approximately 20 kHz. designing and using audio signals. making traditional data compression and prediction processes ineffective at compressing digital audio.
Audio Compression
Audio compression is a technique for converting or encoding audio (sound) information so that a smaller amount of information elements or reduced bandwidth is required to represent. An example of transcoding is the conversion of MP3 audio coding into AAC audio coding. perceptual coding and voice coders. When digital signals are converted from one digital format to another. the ear is most sensitive to sounds in the 1 kHz to 5 kHz. The characteristics and limitations of human hearing can be taken advantage of when selecting.

Waveform coders are capable of compressing and decompressing voice audio.
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. Perceptual coding can take an advantage of the inability of human senses to capture specific types of information.
Waveform Coding
Waveform coding consists of an analog to digital converter and a data compression circuit that converts analog waveform signal into digital signals that represent the waveform shapes. Frequency Masking Frequency masking is the process of blocking. For example. compression ratio also refers to the amount of bandwidth-reduction achieved. removing or ignoring specific frequency components of a signal. it would not be necessary to send signals that cannot be heard even if the original signal contained multiple audio components. 4:1 compression of a 64 kbps channel is 16 kbps. Temporal Masking Temporal masking is the process of blocking. Perceptual coding may remove frequency components (frequency masking) or sequences of sounds (temporal masking) that a listener cannot hear.IPTV Basics
1/4th its original size can be expressed as 4:1. music and other complex signals such as fax or modem signals.
Perceptual Coding
Perceptual coding is the process of converting information into a format that matches the human senses ability to perceive or capture the information. the human ear cannot simultaneously hear loud sounds at one tone (frequency) and soft sounds at another tone (different frequency). Using perceptual coding. For example. removing or ignoring specific components of a signal that occur in a specific time period or time sequence. In telecommunications.

8 shows some of the frequency and temporal masking and techniques that can be used for audio compression. The compressor may also remove low amplitude signals that occur simultaneously with other frequencies (frequency masking).
Figure 4. Perceptual Audio Compression
Voice Coding
A voice coder is a digital compression device that consists of a speech analyzer that converts analog speech into its component speech parts. Voice coders are only capable of compressing and decompressing voice audio signals.
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. This example shows that the compression process may remove small sounds that occur directly after a louder sound (temporal masking).8. This diagram shows that the compression process may remove some audio information that the listener cannot hear. Compression systems may also ignore small changes in sound level.Chapter 4
Figure 4. A speech decoder recreates the speech parts back into their original speech form.

9. the word “HELLO” is digitized. In this example. and the data transmission rate determine the quality of the audio and how much complexity (signal processing) that is required to process the audio signal.
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. This digital information is analyzed and it is determined that this entire word can be represented by three sounds: “HeH” + “LeL” + “OH. The initial digitized bits represent every specific shape of the digitized word HELLO.9 shows the basic digital speech compression process.” Each of these sounds only requires a few digital bits instead of the many bits required to recreate the entire analog waveform. Higher compression typically results in an increase in the complexity of the coding device. To gain an increased amount of compression. Higher complexity (increased signal processing) generally increases the cost and power consumption of the coding device. Digital Speech Compression
The type of audio coder. its analysis functions.
Figure 4. additional signal analysis and processing is usually required.IPTV Basics
Figure 4.

error protection bits may be added to the more significant bits of the compressed audio stream to maintain the audio quality when errors occur. Increasing the amount of perceptual coding (higher compression) increases the amount of time it takes to process the signal (processing delay). the compression process used and the parameters selected for the compression process. The process of audio coding results in delays in the transmission of the digital audio signal and different types of audio coders (different processing techniques) require varying amounts of time for analysis and compression.Chapter 4
The data transmission rate for a compressed audio signal is determined by the audio sampling rate. Audio fidelity is the degree to which a system or a portion of a system accurately reproduces at its output the essential characteristics of the signal impressed upon its input. For example.
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. The sampling rate of an audio signal is typically performed at least 2x the highest frequency contained within the audio signal. small errors that occur during transmission can produce dramatically different sounds. errors that occur on some of the audio data bits (e. Some types of audio coders are designed and configured for applications that require low transmission delays (such as real time telephone communication).41 Mbps. high volume levels or key frequency tones) can be more sensitive to the listener than errors that occur on other data bits. amount of bits per sample. As a result. Typically. In some cases. there is a tradeoff between perceptual coding and processing delay.100 samples per second and each sample produces 16 bits of data and raw uncompressed digital audio at 1. The sampling rate and coding process is a key factor in determining the audio quality or fidelity of the audio signal. a sampling rate of at least 20k samples per second is required. Because audio coders compress information or data into codes and these codes represent tones or other audio attributes. two channels of audio that are sampled at 44.g. This means if you want to convert an audio signal with a frequency range up to 10 kHz.

The next step is to analyze the signal into key parts or segments and to represent the digital audio signal with a compressed code. This diagram shows that the audio coding process begins with digitization of audio signals.10. The compressed code is transmitted to the receiving device that converts the code back into its original audio form.IPTV Basics
Figure 4.
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. Audio Codec Operation
IP Audio Transmission
IP audio transmission is the transport of audio (changing audio levels) that is in the form of data packets to a receiver through an IP data network.
Figure 4. transferring as the audio is played (audio streaming) or played as soon as enough of the media has been transferred (progressive downloading).10 shows the basic operation of an audio codec. IP audio can be downloaded completely before playing (file downloading).

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. Audio streaming can be transmitted with or without flow control. a server system will deliver a stream of audio (usually compressed) to a client. Internet audio streaming systems are used for delivering audio from 2 kbps (for telephone-quality speech) up to hundreds of kbps (for audiophile-quality music). Upon request. Figure 4. Some of the packets are lost at the receiving end of the connection because of the access device. decode the audio and play it to a user.
Audio Synchronization
Audio synchronization is a process that adjusts the timing of the audio signals to match the presentation of other media (such as video or a slide presentation). The client will receive the data stream and after a short buffering delay. When an audio streaming session can receive feedback from the receiver. the audio server may adjust its transmission rate to compensate for changes in the data connection rates.11 shows how an audio server can adjust its data transmission rate to compensate for different audio streaming data rates. This example shows how an audio server is streaming packets to an end user (for an Internet audio player). The audio streaming process may use automatic rate detection or manual rate selection to control the audio streaming transmission rate. indicating that the communication session is experiencing a higher than desirable packet or frame loss rate. The receiving device (a multimedia PC) sends back control packets to the audio server.Chapter 4
Audio Streaming
Audio streaming is the continuous transfer of information that is sent through a communications network that can be represented in the audio frequency band. The audio server can use this information to change the amount of audio compression and data transmission rates to compensate for the slow user access link.

Audio Synchronization
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Figure 4.12.12 shows how audio may be synchronized with a video signal.11. This diagram shows that multiplexed channels can include a program clock reference (PCR) time stamps to allow all of the media streams to remain time synchronized with each other.IPTV Basics
Figure 4. Audio Streaming
Figure 4.

This diagram shows how the web audio server must transfer the entire media file to the media player before audio playing can begin.Chapter 4
File Downloading
File downloading is the transfer of a program or of data from a computer server to another computer.
Figure 4. Figure 4.13.13 shows how to download audio through the Internet. Digital Audio File Downloading
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. File downloading commonly refers to retrieving files from a media server (such as web site server) to another computer.

the result may be very different sounds (a “warble”) due to the use of codebooks. packet corruption and echo (for two-way systems). Packet loss and packet corruption errors will result in distortion or muting of the audio signal. Some of the measures of audio quality include fidelity. Audio coders that have high compression ratios (high efficiency) tend to be more sensitive to packet loss and errors. crosstalk.
Digital Audio Quality (DAQ)
Digital audio quality is the ability of a speaker or audio transfer system to recreate the key characteristics of an original digital audio signal. HTTP streaming manages the sequential transferring of media files through an IP data network (such as the Internet) using HTTP commands that allows media to be played before the transfer is complete.
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. An example of progressive downloading is HTTP streaming. Audio compression devices reduce the data transmission rate by approximating the audio signal and this may add distortion. Muting is the process of inhibiting audio (squelching). packet loss. Even when small amounts of errors occur in a speech coder. The type of audio coder that is used along with its compression parameters influences digital audio quality. noise level and signal to noise ratio. frequency response.IPTV Basics
Progressive Downloading
Progressive downloading is transferring of a file or data in a sequential process that allows for the using of portions of the data before the transfer is complete. Digital audio and transmission system impairments include codec (compression) type. The warble sound results from the creation of different sounds than were originally sent. Warbles are sounds that are produced during the decoding of a compressed digital audio signal that has been corrupted (has errors) during transmission. The compression type influences the amount of distortion that occurs with packet loss or bit errors. total harmonic distortion. Muting can be automatically performed when packet loss is detected.

Figure 4.14.14 shows some of the causes and effects of audio distortion in IP audio systems. Echo results from some of the caller’s audio signal being sent back (audio feedback) by the receiver of the call. Packet corruption results in the creation of a different altered sound than the sound that was previously transmitted.
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. IP Audio Distortion
Audio Fidelity
Audio fidelity is the degree to which a system or a portion of a system accurately reproduces at its output the essential characteristics of the signal impressed upon its input.Chapter 4
Figure 4. This example shows that packet loss results in the temporary muting of the audio signal.

This diagram shows that the same reference test signal is applied to the input of the system and to a comparator. transmission and recreation of an audio signal.15.
Figure 4. Frequency response in digital audio systems is typically limited to one half the sampling frequency (Nyquist limit).15 shows how to measure audio fidelity. Frequency response is expressed as a frequency range with a specified amplitude tolerance in decibels. The comparator removes the original reference signal to show the amount of distortion that is added in the transmission and processing of the signal.IPTV Basics
Figure 4. This diagram shows that fidelity testing can identify the distortion that is added at various places in the recording.
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. Audio Fidelity Testing
Frequency Response (FR)
Frequency response is a measure of system linearity or performance in reproducing signals across a specified bandwidth.

Crosstalk
Cross talk is the transferring of audio from one communications channel onto another channel. The audio test signal is then removed and the energy level at the receiving end is measured (the noise) and recorded.Chapter 4
Total Harmonic Distortion (THD)
Total harmonic distortion is a ratio of the combined amplitudes of all signals related harmonically to the amplitude of a fundamental signal. The energy level at the receiving end is measured and recorded. The difference between these two levels (commonly converted to dB) is the signal to noise ratio.
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Noise Level
Noise level is a measure of the combined energy of unwanted signals. THD is typically expressed as a percentage of signal level.
Signal to Noise Ratio (SNR)
Signal to noise ratio is a comparison of the information-carrying signal power to the noise power in a system. Noise level is commonly specified as a ratio (in decibels) of noise level on a given circuit as compared to decibels above reference noise level for an electrical system or decibels sound pressure level for an acoustical system. Crosstalk is typically expressed as a measure of isolation in decibels between a desired channel and another channel. a connection is setup and a test audio signal is applied to the transmitter. For SNR testing.

g. Some of the common multimedia file formats include media streams.
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. A file container may hold the raw data files (e. Digital audio formats can be a raw media file that is a collection of data (bits) that represents a flow of sound information or it can be a container format that is a collection of data or media segments in one data file. digital audio and digital video) along with descriptive information (meta tags).
Wave Audio (WAV)
Wave audio is a waveform coding for digital audio. indexes. blocks of digital audio and digital audio) within a block of data (file) or as organized on a sequence (stream) of information. MIDI contains voice triggers to initiate the creation of new sounds that represent musical notes. MIDI file size is usually much smaller than other types of audio files. playlists and display control protocols. Wave files are uncompressed so they have a relatively large file size as compared to other types of compressed audio files such as MP3.
Musical Instrument Digital Information (MIDI)
Musical instrument digital information is an industry standard connection format for computer control of musical instruments and devices. Wave audio files commonly have a.g. WAV extension to allow programs to know it is a digital audio file in Wave coding format. File formats can range from simple linear (time progressive) sequences to indexed multiple file formatted blocks of data (containers).IPTV Basics
Digital Media Formats
Digital media file formats are the sequencing and grouping of media information elements (e. Because MIDI files only contain trigger information and not the actual encoded media. container files.

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. their locations and the necessary parameters to setup multimedia communication sessions. Real (.
Real Media (RM.WMA.ra. RAM)
Real Audio (RA) is Real’s (the company) digital multimedia file format that is used to stream digital audio. Real audio files can have the file extension . RA.Chapter 4
Audio Interleaved (AVI)
Audio interleaved (AVI) is a Microsoft multimedia digital audio format that interleaves digital audio and digital audio frames into a common file. Real Media (RM) is a digital multimedia file format that is used to stream digital audio and digital video.WMV or . The format was designed to be an efficient form of streaming and works with Real media players. AVI files contain an index file of the media components. ASF files have the ability to synchronize digital audio and digital video along with managing other forms of media.
Advanced Streaming Index (ASX)
Advanced streaming index is a listing of the media files.rm) files have the ability to synchronize digital audio along with managing other forms of media. ASF is branded as Windows Media and the file extensions it may use include .
Advanced Streaming Format (ASF)
Advanced streaming format is a Microsoft digital multimedia file format that is used to stream digital audio and digital audio.

MPEG Layer 1 (MP1) MPEG layer 1 audio is a low complexity audio compression system. MPEG Layer 2 (MUSICAM – MP2) MPEG layer 2 audio is a medium complexity audio compression system which is also known as the MUSICAM system. This process divides the digital audio signal into multiple frequency bands and only transmits the audio bands that can be heard by the listener. A new version of MPEG audio coder has been created (advanced audio codec-AAC) that offers better audio quality at lower bit rates. To obtain high fidelity quality (e.IPTV Basics
MPEG
MPEG is an industry standard that allows for the use different types of audio coders. To obtain high fidelity quality (e. MPEG Layer 3 (MP3) MPEG layer 3 is a lossy audio coding standard that uses a relatively highcomplexity audio analysis system to characterize and highly compress audio signals. The MUSICAM system is used in the (DAB) digital audio broadcasting system. music) with MP2 typically requires 128 kbps per audio channel.real time telephony).. broadcast radio -vs. The MP3 system achieves high-compression ratios (10:1 or more) by removing redundant information and sounds that the human ear cannot
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.g. coding these sub bands and multiplexing them together. The type of coder that is selected can vary based on the application (such as playing music or speech) and the type of device the audio is being played through (such as a television or a battery operated portable media player).g. dividing the audio signal into sub bands. MPEG speech coders range from low complexity (layer 1) to high complexity (layer 3). music) with MP1 typically requires 192 kbps per audio channel. MP1 was the first digital audio and it uses the precision adaptive sub-band coding (PASC) algorithm. The MUSICAM system achieves medium compression ratios. The AAC coder also has several variations that are used in different types of applications (e.g.

The design of the Layer 3 (MP3) codec was constrained by backward compatibility with the Layer 1 and Layer 2 codecs of the same family. compared with 192 kbps for MP3.
Advanced Audio Codec (AAC™)
Advanced audio codec (AAC) is a lossy audio codec standardized by the ISO/IEC Moving Picture Experts Group (MPEG) committee in 1997 as an improved but non-backward-compatible alternative to MP3. The AACPlus system has multiple streams of audio information which are composed of a base stream that can be combined with another stream to adjust (improve) the characteristics of the high-frequency audio signal components.Chapter 4
detect or perceive. MPEG Layer 3 Pro (MP3Pro) MP3Pro is the Motion Picture Experts Group Layer 3 (MP3) system with spectral band replication (SBR) added to improve audio quality and/or lower the necessary data transmission rate. Like MP3. The AACPlus system uses spectral band replication to improve the audio quality when possible.g. Advanced Audio Codec Plus (AAC Plus™) Advanced Audio Codec Plus is a version of the AAC coder that is used to provide enhanced audio quality at high frequencies. The removal of information components that cannot be detected (such as low level signals that occur simultaneously with high-level signals) is called psychoacoustic compression. The ISO/IEC Moving Picture Experts Group (MPEG) Committee standardized the MP3 codec in 1992. music) with MP3 typically requires 64 kbps per audio channel. To obtain high fidelity quality (e. MP3 is intended for high-quality audio (like music) and expert listeners who have found some MP3-encoded audio to be indistinguishable from the original audio at bit rates around 192 kbps.
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. AAC is intended for high-quality audio (like music) and expert listeners have found some AAC-encoded audio to be indistinguishable from the original audio at bit rates around 128 kbps.

XIPH.
Audio File Format (AU)
Audio file format is a media structure that contains a header and media content section.org for digital audio and digital video. error detection capability along with the insertion of timestamps that can be used to synchronize streams. have multiple channels and the media content can be encoded in multiple encoding formats (such as PCM or ADPCM).IPTV Basics
High Efficiency Advanced Audio Codec (HE AAC) HE ACC is a version of the MPEG AAC system with spectral band replication (SBR) added to improve audio quality and/or lower the necessary data transmission rate. The Ogg file format structure is stream oriented allowing it to be easily used for media streaming applications.org. More information about Ogg and supporting protocols can be found at www. Ogg is an open royalty free standard which is available for anyone to use. AU files can contain descriptive information. Advanced Audio Codec Low Delay (AAC LD) ACC LD is a version of the MPEG AAC system that is designed to provide good audio quality while providing a maximum signal processing delay that does not exceed 20 msec. The container format allows for the ability to interleave audio and video data and it includes framing structure.
Ogg
Ogg is a digital multimedia file container format that was developed by ziph.
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Windows Media Audio (WMA)
Windows media audio is an audio codec format that was created by Microsoft that works with later versions of Windows media player and integrates advanced media features such as digital rights media (DRM) control capability.

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Chapter 5
Motion Picture Experts Group (MPEG)

Motion picture experts group (MPEG) standards are digital video encoding processes that coordinate the transmission of multiple forms of media (multimedia). MPEG is a working committee that defines and develops industry standards for digital video systems. These standards specify the data compression and decompression processes and how they are delivered on digital broadcast systems. MPEG is part of International Standards Organization (ISO). The MPEG system defines the components (such as a media stream or channel) of a multimedia signal (such as a digital television channel) and how these channels are combined, transmitted, received, separated, synchronized and converted (rendered) back into a multimedia format. The basic components of a MPEG system include elementary streams (the raw audio, data or video media), program streams (a group of elementary streams that make up a program) and transport streams that carry multiple programs. Figure 5.1 shows the basic operation of an MPEG system. This diagram shows that the MPEG system allow multiple media types to be used (voice, audio and data), codes and compresses each media type, adds timing information and combines (multiplexes) the media channels into a MPEG pro-

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gram stream. This example shows that multiple program streams (e.g. television programs) can be combined into a transport channel. When the MPEG signal is received, the program channels are separated (demultiplexed), individual media channels are decoded and decompressed and they are converted back into their original media form.

Figure 5.1., MPEG System

The MPEG system has dramatically evolved since 1991 when it was introduced primarily for use on compact disk (CD) stored media. The first version of MPEG, MPEG-1, was designed for slow speed stored media with moderate computer processing capabilities. The next evolution of MPEG was MPEG-2, which allowed television broadcasters (such as television broadcasters, cable television and satellite television providers) to convert their analog systems into more efficient and feature rich digital television systems.

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Since its introduction, the MPEG-2 system has evolved through the use of extensions to provide new capabilities. The term MPEG-2.5 is a term commonly used to describe an interim generation of MPEG technology that provides more services and features than MPEG-2 but less than the MPEG-4. The development of an MPEG-3 specification was skipped. MPEG-3 was supposed to be created to enhance MPEG-2 to offer high definition television (HDTV). Because HDTV capability was possible using the MPEG-2 system, MPEG-3 was not released. The next progression of MPEG technology was the release of the initial parts of the MPEG-4 specification. The MPEG-4 specification allows for television transmission over packet data networks such as broadband Internet. The initial release of the MPEG-4 system did not offer much improvement over the MPEG-2 video compression system. To develop this more efficient video compression technology for MPEG-4, a joint video committee was created. This joint video committee was composed of members from the IETC and ITU for the purpose of analyzing, recommending and solving technical issues to create an advanced video compression specification. The result of this joint effort was the production of the advanced video coder (AVC) that provides standard definition (SD) quality at approximately 2 Mbps. This new part of MPEG-4 video compression (part 10) technology is approximately 50% more efficient (higher compression ratio) than MPEG-2 video coders. The version of AVC defined by the ITU is called H.264. Figure 5.2 shows how the video coding developed for MPEG-4 was a joint effort between the ISO/IEC and United Nations ITU. Both groups worked together to produce the video coding standard. The ISO/IEC version is called advanced video coding (AVC) and the ITU version is called H.264.

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Figure 5.2., MPEG Joint Video Committee

There are other MPEG industry standards including MPEG-7, which is adds descriptions to multimedia objects and MPEG-21, which adds rights management capability to MPEG systems. Figure 5.3 shows how MPEG systems have evolved over time. This diagram shows that the original MPEG specification (MPEG-1) developed in 1991 offered medium quality digital video and audio at up to 1.2 Mbps, primarily sent via CD ROMs. This standard evolved in 1995 to become MPEG-2, which was used for satellite and cable digital television along with DVD distribution. The MPEG specification then evolved into MPEG-4 in 1999 to permit multimedia distribution through the Internet. This example shows that work continues with MPEG-7 for object-based multimedia and MPEG-21 for digital rights management.

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Figure 5.3., MPEG Evolution

Digital Audio
Digital audio is the representation of audio information in digital (discrete level) formats. The use of digital audio allows for more simple storage, processing and transmission of audio signals. MPEG systems can transfer several channels of digital audio. Because audio information is in a continuous analog form, analog audio signals are converted to digital (digitized) to allow them to be more processed and transmitted through digital networks (such as the Internet). To convert analog audio signals to digital form, the analog signal is digitized by using an analog-to-digital (pronounced A to D) converter. The A/D converter periodically senses (samples) the level of the analog signal and creates a binary number or series of digital pulses that represent the level of the signal. The typical sampling rate for conversion of analog audio signals ranges from 8,000 samples per second (for telephone quality) to 44,000 samples per second (for music quality).

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Figure 5.4 shows the basic audio digitization process. This diagram shows that a person creates sound pressure waves when they talk. These sound pressure waves are converted to electrical signals by a microphone. The bigger the sound pressure wave (the louder the audio), the larger the analog signal. To convert the analog signal to digital form, the analog signal is periodically sampled and converted to a number of pulses. The higher the level of the analog signal, the larger the numbers of pulses are created. The number of pulses can be counted and sent as digital numbers. This example also shows that when the digital information is sent, the effects of distortion can be eliminated by only looking for high or low levels. This conversion process is called regeneration or repeating. The regeneration progress allows digital signals to be sent at great distances without losing the quality of the audio sound.

Figure 5.4., Digital Audio

When audio signals are digitized, the amount of raw digital data that is produced can be large. This presents a disadvantage and limitation when storing or transferring the raw data signals. To overcome this challenge, audio compression is used. Audio compression is a technique for converting or encoding information so that smaller amount of information elements can be used to represent the

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audio signal. This allows a reduced amount of bits or lower data transmission rate to store transfer digital audio signals. A sound system may use one (mono) or several audio signals (stereo or surround sound). Stereo is the generation and reproduction of a 2-channel sound source. Stereo signals may be transmitted through the use of independent channels or be sent by sending a single (mono) channel along with difference signal(s). Sound reprodag_MPEG_Evolution>uction that surrounds the listener with sound, as in quadraphonic recording has 4 channels. Additional audio channels include a center channel and a sub audio (very low frequency) channel. The MPEG system has the capability to send one or multiple audio channels along with other media (such as audio and video). Figure 5.5 shows how MPEG allows multiple channels of audio. This example shows that MPEG audio may include left channel, right channel, center channel, left channel surround sound and right channel surround sound. Each of these audio channels are digitized and coded using either level 1 (low complexity), level 2 (medium complexity MUSICAM) or level 3 (high complexity MP3) coding. These channels are combined and multiplexed onto MPEG transport packets. When they are received, they are separated, decoded, and converted from digital back into their original analog form.

Figure 5.5., MPEG Audio

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MPEG systems use audio compression to convert or encode audio (sound) information so that a smaller amount of information elements or reduced bandwidth is required to represent, store or transfer audio signals. The MPEG system supports several types of audio compression and each type can have a different amount of compression. Figure 5.6 shows the different types of audio compression used in MPEG systems and the relative amount of compression that they can provide. This table uses a 2 channel stereo signal that is sampled at 44.1k samples per second, 16 bits per sample as a reference. The MPEG layer 1 coder can compress this signal to approximately 384 kbps (4:1 compression). The MPEG layer 2 coder can compress the signal to 192 kbps (8:1 compression). The MP3 coder can compress the signal to 128 kbps (12:1 compression). The AAC coder can compress the signal to 96 kbps (16:1 compression).

Figure 5.6., MPEG Audio Compression Comparison

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Figure 5.
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. Each position on filtered image is scanned or sampled and converted to a level. through the use of image scanning) that is transferred to a digital video receiver.g. Sending a digital video sequence involves the conversion of a sequence of images to digital information (e. Each sampled level is converted into a digital signal. For color images.Chapter 5
Digital Video
Digital video is a sequence of picture signals (frames) that are represented by binary data (bits) that describe a finite set of luminance (brightness) and chrominance (color) levels. The formats of digital video can vary and the MPEG systems are designed to carry various forms of digital video. There are several ways that digital images and video may be processed (such as progressively sending images or interlacing adjacent images). each line of image is divided (filtered) into its color components (red. green and blue components). Video images are composed of image elements (pixels) that contain brightness (intensity) and color (chrominance) information. Video signals can be converted into digital form by either converting the combined (composite) analog video signal (intensity and chrominance levels) or by representing each image (frame) of the video by its digital pixel elements. The digital information contains characteristics of the video signal and the position of the image that will be displayed. Intensity or luminance is the amount of visible optical energy (intensity) and is measured in Lumens. The MPEG system was designed to allow the transmission of several different digital video formats. Chrominance is the portion of the video signal that contains the color information (hue and saturation).7 shows a basic process that may be used to digitize images for pictures and video.

Figure 5. The MPEG system supports many types of video compression.8.7. MPEG Video Codec Comparison
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.8 Mbps for standard definition (SD) television and 19 Mbps for high definition (HD) television.IPTV Basics
Figure 5. Video Digitization
Digital video compression is the reduction of the number of digital bits required to represent a video signal by digital coding techniques. The MPEG4 AVC video coding system requires approximately 1. a digital video signal can be transmitted on circuits with data rates relatively 50 to 200 times lower than their original uncompressed form. This diagram shows that the standard MPEG-2 video compression system requires approximately 3..8 Mbps for SD television and 6 to 8 Mbps for HD television.
Figure 5..8 shows comparison of MPEG-2 and the new MPEG-4/AVC video coding system. When compressed.

This type of distribution system provides for relatively high and stable transmission rates with minimum delays and low amounts of errors. cable television. Packet broadcast systems often provide variable data transmission rates with varying amounts of delay. MPEG media may be distributed through a variety of types of distribution systems including stored media (such as CD ROMs or DVDs). satellite systems and digital terrestrial television (e. low error rate stored media systems (e. land based (terrestrial) television broadcast.g. Broadcast systems can provide continuous high data transmission rates with small amounts of delay and low bit error rates (called Quasi error free). MPEG-2 was developed to allow transmission over broadcast networks such
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. and interconnecting lines that are used to transfer information to users. DVB). MPEG-1 was designed for stable error free stored media such as CD ROMs. Examples of broadcast systems include cable systems. high error rate mobile video. Figure 5. The next version of MPEG (MPEG-2) was designed for broadcast distribution systems.Chapter 5
Distribution Systems
Distribution systems are the equipment. The original MPEG system (MPEG-1) was first developed for stored media (CD ROMs) distribution systems. Packet broadcast channels can sometimes experience high bit error rates. Examples of packet broadcast systems include broadband television (Internet television) and mobile video.9 shows some of the types of distribution systems that are used to transfer MPEG. Stored media systems have high-transfer rates and very low error rates. software. satellite transmission or through wired or mobile packet data networks. MPEG then evolved to provide television signals over packet data broadcast distribution systems (MPEG-4).g. CD ROM) to limited bandwidth. This example shows that MPEG media may be delivered on systems that range from high bandwidth. The characteristics of these types of distribution systems vary and this requires the MPEG system to use different options to ensure the viewer obtains the media with reliable and expected characteristics.

unpredictable delays and may experience significant amounts of burst error rates.9. MPEG systems are composed of various types of streams ranging from the basic raw data stream (elementary streams) to stream that contain a single television video (a program stream) or a stream that combines multiple programs (transport streams).. These packet data systems usually have variable data transmission rates. to add the
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. A media stream may be continuous (circuit based) or bursty (packetized). The MPEG-4 system was developed to allow transmission over packet data networks such as the Internet.IPTV Basics
as satellite systems. These broadcast systems have some errors and small delays.
Figure 5. The key elements to streaming in the MPEG system include combining multiple packet streams into a single program or transport stream. digital terrestrial television (DTT) and cable television systems. MPEG Distribution Systems
Media Streams
A media stream is a flow of information that represents a media signal (such as digital audio or digital video).

Media Streaming
Elementary Stream (ES)
Elementary streams are the raw information component streams (such as audio and video) that are part of a program stream. This diagram shows that media streaming involves converting media into a stream of packets.Chapter 5
time reference information into the streams and to manage the buffers required to receive and process the elementary streams.
Figure 5.
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. audio or data and there may be several elementary streams for each type of media (such as multiple audio channels for surround sound).10 shows the basic process of streaming video programs through a packet data network. Figure 5. MPEG system divides a multimedia source component into an elementary stream (ES).. Elementary streams may be video.10. . periodically inserting time references and controlling temporary buffer sizes.

PES streams may include time decoding and presentation time stamps that help the receiver to decode and present the media. longer packets may be used. A presentation time stamp is reference timing values that are included in MPEG packet media streams (digital audio. The packet size for program streams can have different lengths. For media distribution systems that have a low error rate. PES packets are variable length packets that have a length limited determined by 16 bits length field in the header of each packet.IPTV Basics
Packet Elementary Stream (PES)
A packet elementary stream is a raw information component stream (such as audio and video) that has been converted to packet form (a sequence of packets). This packet header includes a packet identification code (PID) that uniquely identifies the packetized elementary stream from all other packetized elementary streams that are transmitted. A program stream is called single program transport stream (SPTS). shorter packet lengths are typically used.
Program Stream (PS)
A program stream is a combination of elementary streams (such as video and audio) that compose a media program (such as a television program). All the packets in a program stream must share the same time reference system time clock (STC).
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. For media distribution systems that have medium to high error rates (such as radio transmission or Internet systems). This packetization process involves dividing (segmenting) a group of bits in an elementary stream and adding packet header information to the data. video or data) that are used to control the presentation time alignment of media. Decoding time stamps are the insertion of reference timing information that indicates when the decoding of a packet or stream of data should occur.

A program (such as a television show) is usually composed of multiple PES channels (e. to identify the programs carried on a MPEG-TS. A payload unit start indicator (PUSI) flag alerts the receiver if the packet contains the beginning (start) of a new PES.11 shows an MPEG transport stream and a transport packet structure. The 13 bit packet identifier (PID) is used to define which PES is contained in the packet. This is followed by an error indication (EI) bit that identifies there was an error in a previous transmission process. video and audio). Figure 5. The transport priority indicator identifies if the packet has low or high priority. A packet identifier in an MPEG system identifies the packetized elementary streams (PES) of a program channel. MPEG transport streams (MPEG-TS) use a fixed length packet size and a packet identifier identifies each transport packet within the transport stream.g. MPEG transport packets are a fixed size of 188 bytes with a 4-byte header. A MPEG transport stream (MPEG-TS) is also called a multi-program transport stream (MPTS). The scrambling control flag identifies if the data is encrypted. Because MPEG-TS carry multiple programs. This diagram shows that an MPEG-TS packet is fixed size of 188 bytes
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. These program tables provide a list of programs and their associated PIDs for specific programs which allows the MPEG receiver/decoder to select and decode the correct packets for that specific program. The payload portion of the MPEG-TS packet is 184 bytes. a program allocation table and program mapping table is periodically transmitted which provides a list of the programs contained within the MPEG-TS. An adaptation field control defines if an adaptation field is used in the payload of the transport packet and a continuity counter maintains a count index between sequential packets.Chapter 5
Transport Stream (TS)
Transport Streams are the combining (multiplexing) of multiple program channels (typically digital video channels) onto a signal communication channel (such as a satellite transponder channel). The beginning of a transport packet includes a synchronization byte that allows the receiver to determine the exact start time of the packet.

.IPTV Basics
including a 4-byte header.
Figure 5.11. This example shows that each
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. This example shows how a video and an audio packet elementary stream may be combined onto an MPEG-TS. an adaptation field is used to fill the transport packet. Because the division of PES packets into 184-byte segments will likely result in a remainder portion (segment) that is not exactly 184 bytes. Figure 5. MPEG Transport Stream (MPEG-TS) Packet
PES packets tend to be much longer than transport packets. An adaptation field is a portion of a data packet or block of data that is used to adjust (define) the length or format of data that is located in the packet or block of data. flow control bits. packet identifier (which PES stream is contained in the payload) and additional format and flow control bits.12 shows how PES packets are inserted into a MPEG transport stream. Each packet in the transport stream only contains data from a single PES. The header contains various fields including an initial synchronization (time alignment) field. This requires that the PES packets be divided into segments so they can fit into the 184byte payload of a transport packet.

12. Each PES packet is divided into segments that fit into the transport stream packets..Chapter 5
of the PES packets is larger than the MPEG transport stream packets. Transferring MPEG PES packets into TS Packets
MPEG Transmission
MPEG transmission is the process of combining. A program stream is a combination of elementary streams (such as video and audio) that compose a media program (such as a television program). These channels are statistically combined in such a way that the bursty transmission (high video activity) of one channel is merged with the low-speed data trans-
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. sending and managing the transmission of multiple forms of information (multimedia).
Figure 5. A multi-program transport stream is the combining (multiplexing) of multiple program channels (typically digital video channels) onto a signal communication channel (such as a satellite transponder channel).

MPEG packet sequencing from the encoder is not necessarily the same sequence that is required by the decoder. adjusted in time sequenced using the reference clock and converted back into their original media form. The multiplexer combines these signals and their associated time reference (clock) into a single program transport stream (SPTS). Each media stream is decoded. Basic MPEG Multiplexing
Packet Sequencing
Packet sequencing is the process of organizing packets into a sequence that is in a usable format for the system.IPTV Basics
mission (low video activity) with other channels so more program channels can share the same limited bandwidth communication channel. When the SPTS is received... The decoding and presentation times for frames may not be the same
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. and data onto one data communication channel. This example shows that multiple types of media signals are digitized and compressed and sent to a multiplexer. audio.13.
Figure 5. a demultiplexer separates each of the media signal streams. Figure 5.13 shows how MPEG transmission can be used to combine video.

3) and P frame (4) and I frame (7) are used to produce B frames (5.Chapter 5
because some of the frames may be created from future frames. This diagram shows that because the B frames are created from I frames and P frames. Figure 5.14 shows how the encoder packet sequence differs from the decoder packet sequence. B frames (2. To identify when frames should be presented.3) that are created from the I frame (1) and the future P frame (4) follow this. This example shows an encoder that starts providing a video sequence with a reference I frame (1).6). the sequence of packets provided from the decoder are different.. B frames must be created from P frames and I frames and P frames are created from I frames. MPEG Packet Sequencing
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.
Figure 5. The MPEG system has many types of time stamps including system time stamp (STS).6) that are created follow the P frame (4) and future I frame (7). decoding time stamps (DTS) and presentation time stamps (PTS). This example shows that the output of the decoder is I frame (1) and P frame (4) which are used to produce B frames (2. MPEG system time stamps may be mandatory (such as STS) or optional time stamps (such as DTS and PTS). time stamps are in inserted. B frames (5.14.. The decoder must produce the I frames and P frames before it can produce the B frames.

This
Figure 5. or statistical multiplexing (dynamically assigning portions of channels when activity exists).15.IPTV Basics
Channel Multiplexing
Channel multiplexing is a process that divides a single transmission path into several parts that can transfer multiple communication (voice and/or data) channels. and user data for a television message. audio. code division (dividing into coded data that randomly overlap). and data onto one packet data communication channel. Multiplexing may be frequency division (dividing into frequency bands). A FlexMux is a set of tools that are used by a multimedia system (such as MPEG) that allows for the combining of multiple media sources (such as video and audio) so that the media streams are combined and resynchronized back into its original composite form. audio. This example shows a MPEG channel that includes video. This example shows that multiple types of signals are digitized and converted into a format suitable for the MPEG packetizers.15 shows how MPEG transmission can be used to combine video. Figure 5. time division (dividing into time slots). MPEG Channel Multiplexing
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the different signals are merged back into individual streams.16 shows how multiple MPEG channels may be combined using statistical multiplexing to help average the bandwidth usage.
Statistical Multiplexing
Statistical multiplexing is the process of transferring communication information on an as-needed statistical basis. This example shows 3 MPEG video channels that have variable bandwidth due to high video activity periods (action scenes with high motion). The combined data rate is shown at the bottom. Time slots or codes on a main transmission facility dynamically allocate each communication channel. connections can be initiated and maintained according to anticipated activity need. The multiplexer also combines program specific information that describes the content and format of the media channels.
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. At the receiving end. The combined data rate has a peak data rate that is larger than the 10 Mbps transmission channel can allow. Program channels combined on a MPEG-TS may be statistically combined in such a way that the bursty transmission (high video activity) of one channel is merged with the low-speed data transmission (low video activity) with other channels so more program channels can share the same limited bandwidth communication channel. The multiplexer uses a clock to time stamp the MPEG information to allow it to be separated and recreated in the correct time sequence. A statistical multiplexer can analyze traffic density and dynamically switch to a different channel pattern to speed up the transmission. For statistical multiplexing systems. Figure 5. This allows a communication system to operate more efficiently based by transferring information only when there is activity (such as voice or video signals).Chapter 5
example shows that each media source is packetized and sent to a multiplexer that combines the channels into a single transport stream. As a result.

EPGs can vary from simple program selection to interactive filters that dynamically allow the user to filter through program guides by theme. program components or other information that is related to the delivery and decoding of programs.16.IPTV Basics
one or more of the input MPEG channels must use a higher compression rate (temporary lower picture quality). MPEG tables can be used by electronic programming guides (EPG) to inform the user of the available channels. The EPG is the interface (portal) that allows a customer to preview and select from possible lists of available content media.
Figure 5. or other criteria.. time period.
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. MPEG Statistical Multiplexing
MPEG Program Tables
MPEG tables are groups of structured information that describe programs.

Using the PIDs in the PMT.g. program components (video and audio streams) and conditional access information (to enable decryption and decoding). on-demand programs). the receiver can select and combine the different media components to recreate the television program. The PAT is usually sent every 20 msec to 100 msec to allow the receiver to quickly acquire a list of available programs. The CAT table provides the packet identifier (PID) channel code that provides the entitlement management messages (EMM) to the descrambler assembly.
Program Allocation Table (PAT)
A program allocation table contains the identification codes and system information associated with programs that are contained in a transport stream.
Conditional Access Table (CAT)
A conditional access table holds information that is used by an access device (such as a set top box with a smart card) to decode programs that are part of a conditional access system (e. If any of the programs have conditional access control.
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. the CAT table is transmitted on PID 01.Chapter 5
There are many types of MPEG program tables and the more common tables contain listings of programs in a transport channel (PAT).
Program Map Table (PMT)
Program map table contains information that identifies and describes the components (such as the video and audio elementary streams) that are parts of a program (such as a television show).

17. MPEG Program Tables
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. it will use the information in the table to obtain and classify the elementary stream packets (step 3). a conditional access table (CAT) will be included in the MPEG program stream. This diagram shows that a program allocation table (PAT) is typically sent every 20 msec to 100 msec.17 shows how the MPEG system uses tables to describe programs and the media streams that are contained within the programs.IPTV Basics
Private Tables
Private tables are user defined data elements that are sent along with broadcast programs (such as a television show).
Figure 5. Figure 5. If a program has conditional access rights management associated with it. The PAT provides the information necessary to obtain the program map table (PMT) that a viewer may want to receive. After the receiver has obtained the PMT (step 2). This example shows that the receiver first obtains the PAT (step 1) to obtain the PID of the PMT. The PMT contains the information necessary to receive and decode a specific program and its media components (elementary streams).

Analog television systems use interlacing to decrease the bandwidth required (less picture information) and increase the image presentation rate (increased images per second) to reduce flicker effects.Chapter 5
Video Modes
Video modes are condition of operation that is used to transfer video images.
Frame Mode
Frame mode is the process of sending video as separate images where each image (a frame) in a sequence of a movie adds a complete image. Frame mode is also known as progressive mode.
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. The MPEG system can represent video images in the form of individual images (frame mode) or interlaced images (field mode). field mode or mixed mode. odd and even) to represent each picture scan (fields). Field mode for MPEG was created to allow for the sending of video that is in interlaced form. Interlaced video is a sequence of images (video) that uses alternating graphic lines (e.
Field Mode
Field mode is the process of sending video as images in pairs where each adjacent image (a field) of the pair contains information (image lines) that completes the image in the alternate field. Because some television media is stored in analog video format that use interlacing.g. Converting interlaced video may be performed using frame mode (alternating frames).
Mixed Mode
Mixed mode is a process of converting interlaced video images (fields) into progressive video images (frames). this video must be converted into a format that can be sent on a digital broadcast system.

For one-way systems (such as MPEG-2 broadcast). The accuracy of each of these quantized values determines how close the image block represents the original image. it is possible to reduce the amount of data that represents a block of an image by eliminating the fine details through the use of thresholding. For MPEG systems. Quantizer scaling uses an adjustable
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. Flow control can be used to adjust the transmission rates between devices when one communication device cannot receive the information at the same rate as it is being sent.IPTV Basics
Media Flow Control
Media flow control is the hardware and/or software mechanism or protocol that coordinates the transfer of information between devices.
Quantizer Scaling
Quantizer scaling is the process of changing the quantizer threshold levels to adjust the data transmission rates from a media encoder. MPEG image blocks are converted into their frequency components through the use of discrete cosine transform (DCT). Because many of the frequency components hold small values (small amounts of detail). The use of quantizer scaling allows an MPEG system to provide a fixed data transmission rate by adjusting the amount of media compression. Thresholds are value that must be exceeded for an event to occur or for data to be recorded. This can occur when the receiver requires extensive processing and the receiving buffers are running low. Each frequency component converted (quantized) into a specific value (coefficient). The DCT converts an image map into its frequency components (from low detail to high detail). information may be exchanged between the receiver and the transmitter to adjust the data transmission parameters. media flow control primarily allows for the adjustment of transmission parameters. flow control may be managed by the transmitting end through the use of variable compression rates or for two-way MPEG systems such as MPEG4.

MPEG systems may use bit rate control to adjust the data rate of a MPEG program to match the specific capabilities or requirements of a transmission line.18. This example shows that setting the quantizer level determines if the coefficient data will be sent or if a 0 (no data) will be used in its place.18 shows how MPEG system can use quantizer scaling to control the data rate by varying the amount of detail in an image.Chapter 5
threshold level that determines if the level of frequency component should be included in the data or should a 0 level (no information) be transmitted in its place. This example shows that an image is converted into frequency component levels and that each component has a specific level. Figure 5. MPEG Quantizer Scaling
Bit Rate Control
Bit rate control is a process of setting and/or adjusting the rate of a process or transmission.
Figure 5.
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This diagram shows that the MPEG encoder is required to maintain a data transmission rate of 4 Mbps. If the data transmission rate exceeds the available transmission rate.. action scenes) occur in the video. less changes in video). When the bit rate from the digital video encoder starts to exceed the allowable amount (e. the MPEG transmitter contains a bit rates sensing mechanism. quantizer scaling can be used to reduce the data transmission rate. the encoded data transmission rate increases. action scenes). the maximum data transmission rate of the transmission channel). To perform bit rate control.19 shows how an MPEG system may use quantizer scaling to adjust the data transmission bit rate in an MPEG system.g. The increased quantizer scaling level reduces the detail of the blocks (increased threshold level) and this reduces the data rate.g.IPTV Basics
When significant amounts of motion (e. The tradeoff of higher compression is increased blockiness in the image. the quantizer scaling can be reduced adding detail back into the digital video. This also reduces the detail and accuracy of each block that is transmitted. When the data rate starts to decline (e. MPEG Bit Rate Control
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. This is why digital television programs can display blockiness during periods of rapid changes in video (e. Figure 5.g. the quantizerscaling factor is increased to reduce the data transmission rate.
Figure 5.19. it increases the quantizer scaling level. When the data transmission rate increases. Increasing the quantizer threshold level reduces the amount of data that is sent with each block.g.

The MPEG system has the capability to setup and manage the size of buffers in receivers to allow for variation in data transmission rates. During periods of high video activity. Because this MPEG system has a buffer. some of the data from time periods of high video activity can be deferred into time periods of low activity. The use of buffering allows for variations in the data rate of the digital video while maintaining a constant data transmission rate. the data rate varies. Figure 5.Chapter 5
Buffering
Buffering is an allocation of memory storage that set aside for temporary storage of data.20. The use of memory buffers allows data transfer rates to vary so that differences in communication speeds between devices do not interrupt normal processing operations.. During periods of low video activity. Packet Buffering
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Figure 5.20 shows how packet buffering can be used in MPEG systems to allow for some variations in digital video rates. data from the buffer is consumed at a faster rate than the transmission line can provide which results in the buffer levels decreasing. the data from the buffer is consumed at a slower rate than the transmission line can provide allowing the buffer level to increase. This diagram shows that during the conversion of a digital video signal to an MPEG format.

DSM-CC provides VCR type features. The PCR is a 42-bit field that is transmitted at least every 100 msec.
Real Time Interface (RTI)
Real time interface is an extension to the MPEG system that defines an interface that allows the connection of devices to MPEG bit streams. A PCR is a reference source of timing information that is used as a reference to all the media streams associated with that program. Media synchronization typically involves sending timing references in each media stream that can be used to align and adjust the relative timing of multiple media signals.
Media Synchronization
Media synchronization is the process of adjusting the relative timing of media information (such as time aligning audio and video media). Figure 5.21 shows how MPEG can be used to time synchronize multiple media channels with each other. This diagram shows that MPEG channels include program clock reference (PCR) time stamps to allow all of the elementary streams to remain time synchronized with each other. The variable packet transmission time may result in media components being recreated (rendered) at different times. Media synchronization is especially important for packet based systems that can have variable amounts of delay between media sources.IPTV Basics
Digital Storage Media Command and Control (DSM-CC)
Digital storage media command and control is an MPEG extension that allows for the control of MPEG streaming. a program clock reference (PCR) is used.
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. To provide media synchronization in MPEG systems.

binary format for scenes (BIFS) and active format description (AFD). MPEG Media Synchronization
Display Formatting
Display formatting is the positioning and timing of graphic elements on a display area (such as on a television or computer display). SMIL is a protocol that is used to control the user interface with multimedia sessions.21.Chapter 5
Figure 5. These protocols include synchronized multimedia integration language (SMIL). animation. graphics and interactive controls on a video or television monitor. SMIL is used to setup and control the operation of media files along with the placement and operation windows on the user’s display. Display formatting may combine mixed types media such as video. Binary format for scenes is part of the MPEG-4 standard that deals with synchronizing video and audio.. MPEG has several protocols that can be used to position and sequence the presentation of media. AFD is a set of commands that are sent on a
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MPEG Display Formatting
MPEG-1
MPEG-1 is a multimedia transmission system that allows the combining and synchronizing of multiple media types (e. The use of AFD allows the receiver or set top boxes to adjust or optimize the display for a viewer. Figure 5. there was no defined way to process interlaced video. In the top left.
Figure 5. This example shows a television that has is displaying different types of media.. To the top left.IPTV Basics
video bit stream that describes key areas of interest in a video or image sequence.22.22 shows how MPEG can use BIFS to position and coordinate the timing of media to different areas of a display. a video is streaming in the window area. Because it is primarily focused on multimedia computers.
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. an image of a new game that has been released is shown. On the bottom. The compression processes used in MPEG-1 systems can compress digital video up to 52 to 1. MPEG-1 was primarily developed for CD-ROM multimedia applications. text is display with interactive buttons on the right of each text line. digital audio and digital video).g.

It explains how the audio and video streams are combined into a single data stream and how these streams are separated. The most complex.8 Mbps. part 3 (MP3).5 to 60 Mbps.
MPEG-2
MPEG-2 is a frame oriented multimedia transmission system that allows the combining and synchronizing of multiple media types. level 3 is the origin of MPEG-1. There are 3 levels of audio compression defined in part 3 ranging from the least complex (low compression ratio) to the most complex (highest compression ratio). MPEG-2 is the current choice of video compression for digital television broadcasters as it can provide digital video quality that is similar to NTSC with a data rate of approximately 3. This standard defines the use of spatial (image compression) and temporal (multiple sequences) through the use of image blocks and a prediction on how these blocks will move between frames. Part 3 defines how audio is compressed. The MPEG-2 system was developed to provide broadcast television applications so it has the ability to support progressive and interlaced video formats.
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.5 Mbps. The data rates for MPEG-2 systems can range from approximately 1. The MPEG-2 system defines a digital video encoding process that can compress digital video up to 200 to 1. Part 5 provides software simulations for the MPEG-1 system. decoded and time synchronized. Part 4 defines how bit streams and decoders can be tested to meet MPEG specification requirements.Chapter 5
Part 1 of the MPEG-1 specification defines the overall system operation. Part 2 defines how digital video is coded for compressing video sequences allowing bit rates up to 1.

Part 5 provides software simulations for the MPEG-2 system. The MPEG-2 audio system allows more than 2 channels of audio permitting surround sound applications.
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. This development of this part was discontinued. Part 4 defines how bit streams and decoders can be tested to meet MPEG specification requirements. A Key feature of MPEG-4 is its ability to manage separate media components within image frames. It has the ability to sense and adjust the delivery of media dependent on the media channel type such as fairly reliable broadcast or unreliable Internet. Part 10 contains conformancetesting processes for DSM-CC.
MPEG-4
MPEG-4 is a digital multimedia transmission standard that was designed to allow for interactive digital television and it can have more efficient compression capability than MPEG-2 (more than 200:1 compression). Part 2 describes how programs are combined onto transport streams that can be transmitted over satellite.IPTV Basics
Part 1 of the MPEG-2 system provides overview that defines the media streams and how they are combined into programs. pause and stop the play of media. Part 3 defines the how multiple channel audio can be transmitted on MPEG. Part 7 describes the more efficient advanced audio codec (AAC) which is not backward compatible with previous MPEG audio coding systems. MPEG-4 can model media components into 2 dimensional or 3 dimensional scenes. broadcast television and cable TV networks. Part 6 defines the protocols that can provide media flow commands that can be used by users to start. Part 9 describes how a real interface (RTI) could be used to allow stream decoders to connect to transport streams. These media objects can be independently controlled and compressed more efficiently. Part 8 was created to define how video coding could use 10 bit samples.

Chapter 5

The overall structure and operation MPEG-4 system is described in Part 1. Part 2 defines the original video compression codec that was used in the MPEG-4 system. While this video codec offered an improvement in compression (a small amount) over the MPEG-2 video compression process, it was a relatively small improvement. Part 3 contains a set of audio codecs along with speech coding tools. Part 4 defines the testing and conformance processes that are used to ensure devices meet the MPEG specifications. Part 5 contains reference software that can be used to demonstrate or test the operation of the MPEG-4 system. Part 6 provides the delivery multimedia integration framework (DMIF) structure that allows a multimedia system (such as MPEG) to identify the sources of media and the transmission characters for that media source (such as from a high bandwidth low error rate DVD or through a limited bandwidth mobile telephone system). The use of DMIF allows the playback system to become independent from the sources and their transmission limitations. Part 7 contains reference software that can be used to optimize MPEG systems. Part 8 describes how to send MPEG signals through IP networks. Part 9 provides reference hardware designs that can be used to demonstrate how to implement MPEG solutions. Part 10 is the advanced video coding/H.264 part that provides substantial compression improvements over the MPEG-2 video compression system. Part 11 contains the binary format for scenes part of the MPEG-4 standard, which deals with synchronizing video and audio. Part 12 describes the file format that can be used for storing the media components of a program. Part 13 contains the intellectual property management and protection is a protocol that is used in the MPEG system to enable digital rights management (DRM). Part 14 defines the container file format that can be used for MPEG-4 files. Part 15 defines the file format that can be used to store video that is compressed using the advanced video coder (AVC).

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Part 16 contains the animation framework extension (AFX) set of 3D tools for interactive 3D content operating at the geometry, modeling and biomechanical level. Part 17 defines how text subtitles can be combined and timed with MPEG media. Part 18 defines how fonts can be compressed and streamed. Part 19 describes how to provide synthesized texture streams.

MPEG-7
MPEG-7 is a system that can be used to describe the characteristics and related information about digital media objects. The MPEG-7 system is an XML based language. The MPEG-7 system uses description definition language (DDL) to describe the characteristic objects using existing (standard) and custom created definitions. Some of the standard characteristics include shape, texture and motion. Part 1 of MPEG-7 is an overview of the key tools that are needed to describe media objects in MPEG systems. Part 2 provides the description definition language (DDL) that defines the syntax of the MPEG descriptions and how to extend (create) custom description. Part 3 explains the tools that cover visual descriptions. Part 4 explains the tools that cover audio descriptions. Part 5 defines how to develop multimedia descriptions for objects with generic features. Part 6 contains reference software that can be used to demonstrate and test MPEG-7 systems. Part 7 provides the processes that allow testing to ensure products and software meet the requirements of the MPEG-7 system. Part 8 covers the extraction and use of descriptions. Part 9 contains the profiles and levels for MPEG-7. Part 10 describes the structure (schema) of the description definition language (DDL).

MPEG-21
MPEG-21 is a multimedia specification that adds digital rights management capability to MPEG systems. MPEG-21 is an architecture that enables the searching, selecting, defining and managing the rights associated with digital media objects.

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The MPEG-21 standard parts include digital item declaration (DID), digital item identification (DII), intellectual property management and protection (IPMP), rights expression language (REL), rights data dictionary (RDD) and digital item adaptation (DIA). Part 2 defines digital the common set of terms and descriptions that can define a digital media object. Part 3 explains digital item identification (DII) can uniquely identify any type or portion of content. Part 4 describes the intellectual property management and protection is a protocol that is used in the MPEG system to enable digital rights management (DRM). Part 5 defines how rights expression language (REL) protocol can be used to specify rights to content along with fees or other consideration required to secure those rights. Part is contains the rights data dictionary (RDD). Part 7 covers digital item adaptation (DIA) which defines the semantics and syntax that may be used to adapt the format or transmission of digital items. Part 8 provides reference software that can be used to demonstrate or test the operation of the MPEG-21 system. Part 9 describes file formats.

MPEG Profiles
MPEG profiles are a particular implementation or set of required protocols and actions that enables the providing of features and services for particular MPEG applications. These applications range from providing standard television services over a broadcast system to providing video services on a mobile wireless network. The use of profiles allows an MPEG device or service to only use or include the necessary capabilities (such as codec types) that are required to deliver media to the applications. Profiles are created for specific applications and types of media. New profiles are constantly being requested and created. Because the types of applications of applications that use MPEG transmission can dramatically vary, MPEG has tens of profiles and there are different profile types for the MPEG-2 and MPEG-4 systems.

Simple Profile (SP)
The simple MPEG profile provides video for relatively simple bandwidth limited devices such as mobile telephones and personal digital assistants. The simple profile does not allow the use of bi-directional frames (B-Frames) which keeps the coding complexity low.

Main Profile (MP)
Main profile is a common set of protocols and processes that are used to provide standard television services. The main profile used in the MPEG system allows for the use of Intra frames (I-Frames), predicted frames (PFrames) and bi-directional frames (B-Frames). The MPEG main profile also allows for the incorporation of background sprites, interlacing and object shapes with transparency. The main profile is commonly used for broadcast television applications.

Scalable Profile
Scalable profile is the set of MPEG protocols and processes that can provide video with varying bandwidth and performance needs. The scalable profile defines a base layer along with layers that are used to enhance the quality or performance of a video signal. The scalable profile enables the use of mobile devices that have varying capabilities of reception and display resolution.

High Profile (HP)
High profile is the set of MPEG protocols and processes that are used for high definition television (HDTV). Although the high profile was originally

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developed for HDTV service, the main profile levels were expanded to enable the transmission of HDTV signals using the main profile.

4:2:2 Profile
4:2:2 profile is a set of protocols and process that are used to provide high quality color video for studio production and distribution services. The 4:2:2 contains more color elements than the standard 4:2:0 YUV color format. The 4:2:2 profile allows for the use of I-frames, P-frames and B-frames. At standard resolution (720x576), its maximum data rate is 50 Mbps and at high definition (1920x1080), the maximum data rate is 300 Mbps. Figure 5.23 shows the different types of profiles and how they are used in the MPEG-2 systems. This table shows that the key MPEG-2 profile types include simple, main, scalable, high and 4:2:2 studio profiles. Simple profiles are used for low complexity devices (such as portable media players). The main profile is used for standard broadcast television applications. Scalable profiles offer the ability to provide varying levels of service different types of devices (such as wireless devices). The high profile is used for high definition television. The 4:2:2 profile is used for studio production and distribution.

Audio Profiles
Audio profiles are protocols and processes that are used to provide audio transfer and rendering applications and services. The audio profiles focus on specific applications that require tradeoffs such as the tradeoff of having a high audio compression ratio which results in increased audio processing (coding time) delays and higher sensitivity to transmission errors. Additional tradeoffs include speech coding (optimized for human voice) that can offer a high compression ratio as opposed to natural audio coding with relatively low compression ratios that can reproduce any sound. The MPEG-4 system has several audio profiles including speech profile, synthesis profile, scalable profile, main profile, high quality audio profile, low delay audio profile, natural audio profile and mobile audio internetworking profile. The speech profile can be used to produce a range of speech audio functions ranging from high bit rate waveform coding to very low bit rate text to speech audio coding. Text to speech conversion transforms text (ASCII) information into synthetic speech output. This technology is used in voice processing applications that require the production of broad, unrelated and unpredictable vocabularies, e.g., products in a catalog, names and addresses, etc. Synthesis profile defines how the MPEG system can use wave table synthesis and text to speech to create audio. The scalable profile can use different bit rates and audio bandwidths to effectively provide audio that contains music and speech. Main profile contains tools for natural and synthetic audio.

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High quality audio profile allows for the use of advanced audio coding (AAC) which is more efficient (has a higher data compression ratio) than the MP3 coder. The low delay audio profile uses speech coders and text to speech interfaces to provide low delay real time communication. It is a version of the advanced audio coder that reduces the amount of processing time for coding which can be used for real time two-way communication applications. Natural audio profile contains the capabilities for natural (non-synthetic) audio coding. Mobile audio internetworking profile uses a scalable AAC with low delay to enable high quality audio coding processes for time sensitive applications (such as video conferencing).

Visual Profiles
Visual profiles are protocols and processes that are used to provide video transfer and rendering services. The MPEG-4 system video profiles have capabilities that include the transfer of arbitrarily shaped objects (as opposed to rectangular shaped objects), scalable (variable quality) images, layered (images that can be enhanced) and the transfer and remote (local creation) of animated images. Simple visual profile is a low complexity video coding system that can be used for portable video devices such as multimedia cellular telephones. Because it is a simple profile, it does not include the ability to provide interlaced video. Simple scalable visual profile can carry over multiple sequences (temporal scalability) or over multiple areas (spatial scalability) to allow operation at different bit rates. The fine granularity scalability profile has the ability to layer multiple levels of image quality. It starts with a base layer and ads enhancement layers to improve the resolution of the images. It can be used in systems to offer different quality levels when bandwidth is selectable or adjustable.

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Advanced simple profile (ASP) can use B-frames and can use ¼ pel compensation to increase the compression ratio (it is approximately 1/3rd more effi-

cient than simple visual profile). Core visual profile has the ability to define objects that have different (arbitrary) shapes. It is useful for applications that have interactivity between media objects. The core scalable profile includes improved scalability options for arbitrarily shaped objects. Main visual profile includes the ability to process interlaced video objects. The main visual profile can be used for broadcast and interactive DVD applications. N-bit visual profile defines how to code video objects using pixel depths that range from 4 bits to 12 bits. Advanced core profile includes the ability to process arbitrarily shaped video and still images. Advance coding efficiency profile (ACE) adds tools that can increase the compression ratio for both rectangular and arbitrarily shaped video objects. Simple studio profile is used to maintain the quality of video for studio distribution and editing functions. The studio simple only uses I frames. The core studio profile ads P-frames to the simple studio profile allowing a higher compression ratio at the expense of added complexity. The simple facial animation visual profile uses a mathematical model to animate facial images. This allows for the sending of a very small amount of data (e.g. lips move a small amount) to create 3 dimensional images. The simple face and body animation profile uses a mathematical model to animate both facial and body images. Advanced real time simple (ARTS) uses a low delay coding process along with robust error coding to provide real time two-way communication that cannot tolerate delays and which are subject to high error rates. The scalable texture visual profile allows for the mapping of textures onto images. Basic animated 2D texture visual profile has the capability to insert textures onto 2D images. Advanced scalable texture profile can perform scalable shape coding. This includes wavelet tiling.

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High 10 profile (Hi10P) provides for increased quality allowing up to 10 bits per sample of decoded picture elements. Main
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. The AVC profiles use the H. mobile telephones and portable media players. Cable TV) and storage (e. DVD) applications. High 4:4:4 profile (Hi422P) adds additional chroma (color) elements and allows up to 12 bits per image element.Chapter 5
The hybrid visual profile includes the capability to decode synthetic and natural objects. The main profile was designed for broadcast (e.
MPEG-J Profiles
MPEG-J profiles are protocols and processes that are used to provide application programming interface (API) capabilities to underlying MPEG services. The AVC profiles range from low complexity baseline profile (BP) to an ultra high professional quality 4:4:4 profile. Extended profile (XP) is designed for streaming video over networks that may have high packet loss (such as the Internet). The baseline profile (BP) is used for low complexity device such as portable media players.g.g. Personal MPEG-J profile is used for low complexity portable devices such as gaming devices. High 4:2:2 profile (Hi422P) is used for professional applications that require higher levels of chroma (color) elements.264/AVC coder that provides a compression ratio that is approximately double the MPEG-2 video coder. The MPEG-4 system has several MPEG-J profiles including personal profile and main profile. High profile (HiP) can provide high definition television for broadcast and stored media distribution systems.
Advanced Video Coding Profiles
Advanced video coding profiles are protocols and processes that are used to provide advanced video transfer and rendering capabilities to underlying MPEG services.

Some of the scene graphs profiles are based on the virtual reality modeling language (VRML) protocol. primarily for use with Web browsing. It allows for local animation and interaction. Complete 2D scene graph profile allows for alpha blending and interactivity with the media objects. graphic images and audio components in a 2 dimensional or 3 dimensional enviornment. complete 2D scene graph profile. It is used for audio only or video only applications. The simple 2D scene graph profile can place media objects into a scene on a 2 dimensional area.
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. core 2D profile. Local animation is a process that changes parameters or features of an image or object over time that is processed at the location where the animation is playing (e.
Scene Graph Profiles
Scene graph profiles are the sets of protocols and processes that are used to define a composite (mixture) of media objects and how they relate to each other in an area. The basic 2D profile is used to define simple scenes on a 2 dimensional area. X3D profile. Alpha blending is the combining of a translucent foreground color with a background color to produce a new blended color. main 2D profile. audio scene graph proifle and 3D audio scene graph profile.IPTV Basics
MPEG-J profile includes all the profiles from personal MPEG-J profiles plus APIs that can be used to select and configuring decoders along with interfaces to access service information.g. The MPEG-4 system scene graph profiles include the basic 2D profile. The core 2D profile can use both audio and visual media objects. simple 2D scene graph profile. complete scene graph profile. It is a low complexity profile and it and does not define interaction with the media objects. VRML is a text based language that is used to allow the creation of three-dimensional viewpoints. advanced 2D profile. within a television or multimedia computer). Scene graph profiles can be used to define the hierarchical relationship between videos.

The simple 2D + text profile adds the ability to
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.Chapter 5
The advanced 2D profile contains the capabilities of the basic 2D and core 2D profiles along with adding scripting capability and local interaction. SMIL is a protocol that is used to control the user interface with multimedia sessions. Extensible 3D (X3D) is a storage. The X3D profile is a small footprint (limited memory and processing requirements) 3 dimensional media processing profile. SMIL is used to setup and control the operation of media files along with the placement and operation windows on the users display. core 2D profile. Complete scene graph profile can be used for vitual gaming that have 3 dimensional worlds. The 3D audio scene graph profile describes how to position sound in a 3 dimensional environment. It is designed to interoperate with synchronized multimedia integration language (SMIL).
Graphics Profiles
Graphics profiles are sets of protocols and processes that are used to define and control graphics elements that are used in scenes. and X3D core profile. Complete scene graph profile is a combined set of 2D and 3D scene graph profiles from the binary format for scenes (BIFS) toolbox. The simple 2D graphics profile is used for placing media objects in a scene that has only 2 dimensions. It is designed to interoperate with X3D specification created by the Web3D consortium. Some of the graphics profiles used in MPEG-4 systems include simple 2D graphics profile. comlete graphics profile. The main 2D profile ads FlexeTime model which allows input sensors and additional tools for interactive applications. advanced 2D profile. Audio scene graph profile is used for applications that only require audio media. complete 2D graphics profile. 3D audio graphics profile. It allows for interaction of sounds with objects within the scene. simple 2D + text profile. retreival and rendering (playback) industry standard for real time graphics media objects which can be adjusted in relative position and possibly interact with each other.

Core 2D profile is used for picture in picture (PIP). The X3D core profile includes 3 dimenstional media object processing capabilities for advanced gaming and virtual environments. Figure 5. 3D audio graphics profile is used to define the acoustical properties of a scene. acoustic diffusion. MPEG-4 Profile Types
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. acoustic transparency and tele-presence.
Figure 5. The advanced 2D profile adds graphic user interface (GUI) capabilities along with more complex graphics control for animation.. extrusions and lighitng effects to create virtual worlds.g. Complete 2D graphics profile is a full set of 2D graphics control capabilities including the use of multiple shaped graphic objects.24 shows the different types of profiles used in the MPEG-4 systems. become transparent) with other media objects. video warping. animated advertisements and logo insertion. This table shows that the key MPEG-4 profile types include audio. The complete graphics profile allows for the use of elevation grids.24. It includes features such as acoustics absorption.IPTV Basics
include text on the screen and to allow the text to move and be transformed (e. It is compatible with X3D specification.

MPEG Levels
MPEG levels are the amount of capability that a MPEG profile can offer. The visual profiles range from low resolution profiles that can be used in portable devices to high quality studio profiles. This table shows that low level has low resolution capability with a maximum bit rate of 4 Mbps. Main level MPEG signals provide for resolution of up to 720x576 (standard definition television). MPEG-2 Levels
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.25 shows the different levels used in the MPEG-2 system. This combination provides television signals for standard definition (SD). Figure 5. MPEG-J. Scenes profiles define the relationships between media objects.Chapter 5
visual. One of the more common profile combinations is the main profile at the main level (MP@ML). advanced video. MPEGJ profiles allow the device to have direct programming interfaces to the MPEG media and devices. MPEG levels can range from low detail (low resolution) to very high capability (high resolution). scenes and graphics profiles. The use of levels allows products to define their quantitative capabilities such as memory size. resolution and maximum bit rates. Advanced video coding profiles take advantage of the high compression AVC coder. Low level MPEG signals have a resolution format of up to 360 x 288 (SIF). Graphics profiles define media objects and how they are positioned on displays and how they can be changed in scenes. The audio profiles range from very low bit rate to high quality audio that can be used in cinemas. For example.25.. The main level has standard definition (SD) capability with
Figure 5. High level can support resolution of up to 1920x1152 (high definition).

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. The high 1440 profile is a high definition format that has a maximum bit rate of 60 Mbps. The high level profile has a high definition format with 1152 lines that have 1920 pixels per line which can have a bit rate of up to 80 Mbps. An example of conformance points is if ability of a mobile video server to support creation and playback of a simple visual profile at level 0.IPTV Basics
a maximum bit rate of 15 Mbps.
Conformance Points
Conformance points are a combination of profiles and levels in a system (such as an MPEG system) where different products can interoperate (by conforming to that level and profile). any mobile phone that has these conformance points should be able to play a video with these profiles and levels.

Chapter 6
IP Television Systems
There are three basic types of systems that are used to provide IP television services. Managed IP television systems include IP television over cable.
Internet Television Service Providers (ITVSPs)
Internet television service providers (ITVSPs) supply IP television services to their customers that are connected to broadband Internet connections
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. IP television over cable modem.
Managed IP Television Systems
Managed IP television systems provide services to customers using controlled access Internet protocol (IP) connections. telephone (“Telco TV”). managed IP television. Internet television service provider (ITVSP) and private IP television systems. wireless broadband or digital television over powerline where the IP television provider controls both the access network and the services. it is possible to guarantee the video quality and reliability of the IP television service to the customer. Managed IP television systems allow customers to have the quality and features that are typically associated with a traditional television system (such as cable television – CATV). Because the IP television provider manages (controls) the bandwidth of the access network.

IPTV Basics
(“over the top of the broadband Internet”). The ITVSP receives their requests and determines what features they are authorized to access that particular feature or service. Because ITVSPs provide IP television signals through public broadband networks. if the data links in the connection from the media source to the viewer have data rates that are much higher than the viewer’s data rate. ITVSPs use computer servers to keep track of which customers are active (registration) and what features and services are authorized. These clearinghouses gather all the billing details (which may be hundreds of thousands) of billing records per month for each ITVSP that has used the gateway and create invoices for each ITVSP periodically. ITVSP companies are primarily made of computers that are connected to the Internet and software to operate call processing and other services. the ITVSP sends messages to gateways via the Internet allowing television channels to be connected to the viewer’s media player. the channel quality is likely to be good for the selected digital video signal. ITVSPs can vary from companies that simply provide IP television links to viewers to media content providers. When television channel requests are processed. If the ITVSP decides to provide service.
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. gateways are commonly connected to clearinghouse companies to settle the usage charges. they cannot directly control the quality of service for data transmission. Customers use IP television access devices (media players) or IP set top boxes (self contained media players) to communicate their requests for services and features to the ITVSP. Because there are many television gateways located throughout the world (some television programs may have multiple gateways). While the ITVSP cannot directly control or guarantee IP television quality. ITVSPs provide access screens or channel links to allow the customer to connect their viewers to media sources for a fee. The gateway will record the time and usage information and send it to the ITVSP to account for the usage (to get paid). it will determine which gateway it will use to connect the viewer to the media source.

Chapter 6
Private IP Television Systems
Private IP television systems are used to provide television service within a building or group of buildings in a small geographic area. There are several ways that private television systems (such as CATV systems) can be upgraded for IP television capability. stop. governments throughout the world have eased their regulation of the broadcast industry.
IP Television (IPTV) Networks
IPTV networks are television distribution systems that use IP networks to deliver multiple video and audio channels. For many years. community television. access connections and end user display devices. Severs control the overall system access and processing of calls and gateways convert the IP television network data to signals that can be used by television media viewers. video (television) broadcasters had monopolized the distribution of some forms of information to the general public. fast forward). In 1996. Applications for private IP television systems include hotel television. DVD video players) and/or they may be connected to other media sources through gateways. gateways. Private IP television systems may be directly connected to media sources (e. and advanced television channel selection processing features such as channel selection. surveillance security and video conferencing. media control (play.g. Due to the recent competition of wide area information distribution. and types of services broadcast companies could offer. media gateways. operation. the United States released the Telecommunications Act of 1996 that dramatically deregulated
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. Private IP television systems typically contain media servers. IP Television networks are primarily constructed of computer servers. This had resulted in strict regulations on the ownership. The options range from adding IP television gateways as a media source to allow the existing television systems to receive new television channels to replacing the media sources and set top boxes with IP video devices.

To do this.1. IPTV systems gather content via a content network and convert the content to a format that it can use via a headend system. on multimedia computers or on IP televisions (data only televisions). The asset management system stores. moves and sends out (playout) the media at scheduled times. playout) the content via an asset management system. Users view IPTV programming on analog televisions that are converted by adapter box (IP set top box). IPTV System
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. This allowed almost all types of communication systems to provide many new services with their existing networks including television services.IPTV Basics
the telecommunications industry. stored media. The distribution system simultaneously transfers multiple channels to users who are connected to the IPTV system.1 shows a sample IPTV system.
Figure 6. communication links and live studio sources. It then manages (e. transfers the content via a distribution network. IPTV system operators link content providers to content consumers. Figure 6. The headend converts the media sources into a form that can be managed and distributed. This diagram shows the IPTV system gathers content from a variety of sources including network feeds. and then the media may be displayed on a variety of viewing devices.g.

Connection Types
IPTV content distribution network connection types include satellite connections. A satellite communication link includes a communication link that passes through several types of systems. Satellite content providers combine multiple programs (channels) for distribution to broadcasters. satellite reception and transmission equipment (transponder). education and public sources. Content sources include program networks. downlink path. leased lines. Leased lines often come with a guaranteed level of performance for connections between two points. and reception electronics and antenna. content aggregators and a variety of other government.g. mobile data and public data networks (e. uplink path. Because satellite systems provide signal coverage to a wide geographic area. the high cost of satellites can be shared by many broadcasting companies. IPTV systems receive content from multiple sources through connections that range from dedicated high-speed fiber optic connections to the delivery of stored media. Internet). These connections include the transmission electronics and antenna. Satellite content distributors that provide television programming to IPTV networks via satellite lease some or all of the transponder capacity of the satellite. virtual networks. a television system). Satellite communication is the use of orbiting satellites to relay communications signals from one station to many others.g. microwave. Leased lines are telecommunication lines or links that have part or all of their transmission capacity dedicated (reserved) for the exclusive use of a single customer or company.
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.Chapter 6
Contribution Network
A contribution network is a system that interconnects contribution sources (media programs) to a content user (e. Leased lines may be used to guarantee the transfer of media at specific times.

Each node contains routing tables that provide packet forwarding information. Microwave links are commonly used by IPTV systems to connection remote devices or locations such as a mobile news truck or a helicopter feed.g. The data traveling between two points is usually encrypted for privacy.IPTV Basics
Virtual private networks are private communication path(s) that transfer data or information through one or more data network that is dedicated between two or more points. A microwave link uses microwave frequencies (above 1 GHz) for line of sight radio communications (20 to 30 miles) between two directional antennas. Each node in the Internet forwards received packets to another location (another node) that is closer to its destination. The Internet can be effectively used to privately transfer programs through the use of encryption. the additional of mobility for data communication results in an increased cost for data transmission. The Internet transfers data from point to point by packets that use Internet protocol (IP). computers electronic assemblies) that can transmit data through a mobile communication system (such as a wireless data system or cellular network). The Internet is a public data network that interconnects private and government computers together. Each transmitted packet in the Internet finds its way through the network switching through nodes (computers).
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. Each microwave link transceiver usually offers a standard connection to communication networks such as a T1/E1 or DS3 connection line. In general. Microwave links may be licensed (filed and protected by government agencies) or may be unlicensed (through the use of low power within unlicensed regulatory limits). Mobile data is the transmission of digital information through a wireless network where the communication equipment can move or be located over a relatively wide geographic area. This use of microwave links avoids the need to install cables between communication equipment. Virtual private networks allow the cost of a public communication system to be shared by multiple companies. VPN connections allow data to safely and privately pass over public networks (such as the Internet). The term mobile data is typically applied to the combination of radio transmission devices and computing devices (e.

its descriptive information (metadata) is also delivered. This example shows that programming that is gathered through a contribution network can come from a variety of sources that include satellite connections. Internet) and the use of stored media (tapes and DVDs).
Figure 6. When content is delivered through the content network.2 shows a contribution network that is used with an IPTV system. mobile data. IPTV Contribution Network
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. microwave links.2. Some of the descriptive data may include text that is used for closed captioning compliance.g. The metadata information may be embedded within the media file(s) or it may be sent as separate data files.Chapter 6
In additional to gathering content through communication links. Examples of stored media include magnetic tapes (VHS or Beta) and optical disks (CD or DVDs). leased lines. content may be gathered through the use of stored media. public data networks (e. Figure 6. virtual networks.

IPTV Basics
Program Transfer Scheduling
Program transfer scheduling is the set upand management of times and connection types that media will be transported to the IPTV system. This example shows that the IPTV system may select multiple connection types and transfer speeds.
Figure 6. the faster the data transfer speed. The cost of transferring content can vary based on the connection type (e. IPTV Program Transfer Scheduling
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. the higher the transfer cost.g. In general.3. The scheduling of program transfer during low network capacity usage periods and at lower speed can result in significant reduction in transfer cost. Figure 6. This example shows that the selection can depend on the program type (live versus scheduled) and transfer cost. satellite versus Internet) and the data transfer speed.3 shows how an IPTV system may use transfer scheduling to obtain programs reliably and cost effectively. IPTV systems have a limited amount of media storage for television programs so they typically schedule the transfer programming a short time (possibly several days) before it will be broadcasted in their system.

Examples of local feeds include connection from sportscasts. Examples of helicopter feeds include microwave and private radio connections.
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. Helicopter Feed Helicopter feed is a media connection that is used to transfer content from airborne sources.Chapter 6
Content Feeds
A content feed is a media source that comes from a content provider or stored media system. Local Feed Local feed is a media connection that is used to transfer content from local sources. The types of content feeds that may be used in IPTV systems range from network feeds (popular programming) to video feeds from public events (government programming). Off Air Feed An off air feed is a content source that comes from an antenna system that captures programming from broadcasted radio signals (off air radio transmission). Examples of truck feeds include cellular and microwave connections. The off air feed converts broadcasted radio channels into a format that can be retransmitted on another system (such as an IPTV system). Truck Feed A truck feed is a media connection that is used to transfer content from mobile news vehicle source. Network Feed A network feed is a media connection that is used to transfer media or programs from a network to a distributor of the media or programs. Offair feeds are used to retransmit locally broadcasted content on the IPTV system. news crews and live studio cameras.

election coverage. Syndication Feeds Syndication feeds are media connections or sources that are used to transfer media or programs from a syndicated network to a distributor of the media or programs. An example of a syndicated feed is really simple syndication (RSS) feed. Examples of public programming include local events and subjects that members of a community have an interest in. An RSS feed provides content such as news stories via the Internet. property zoning.
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. health related disease controls and other public information that is related to citizens. Public Access Channel A public access channel is a media source that is dedicated to allowing the public to create and provide programming to a broadcast system. public worker training programs. Examples of educational programming include student programming. distance learning classes. Examples of government programming include legal announcements. Educational Access Channel An educational access channel is a media source that is dedicated to education. RSS content feeds are often commonly identified on web sites by an orange rectangular icon.IPTV Basics
Live Feed A live feed is a media connection that is used to transfer media or programs from a device that is capturing in real time (such as a mobile camera) to a distributor of the media or programs. school sporting events. student artistic performances and the viewpoints and teachings of instructors. Educational programming may come from public or private schools. RSS allows content from multiple sources to be more easily distributed. Government Access Channel A government access channel is a media source that is dedicated to informing citizens of public related information.

the transmission of broadcasting equipment is temporarily shifted to emergency alert messages. syndication (shared sources). This table shows that content sources include off-air local programs. local programs.Chapter 6
Emergency Alert System (EAS) Emergency alert system is a system that coordinates the sending of messages to broadcast networks of cable networks. AM.4 shows some of the different types of content sources that may be gathered through a contribution network. public access (residents). Contribution Network Programming Sources
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. entertainment from national networks. When emergency alert signals are received. FM. Figure 6. and TV broadcast stations. government access channels (public information).
Figure 6.4. Low Power TV (LPTV) stations and other communications providers during public emergencies. and the emergency alert systems. education access.

amplified. To reduce the cost of an IPTV system. video players) are received.. headend systems can be shared by several distribution systems. set top boxes). decoding and decryption functions into one assembly. Headends commonly use integrated receiver devices that combine multiple receiver. local studios. converted into packets and sent into IPTV packet distribution system. and re-modulated onto TV channels for transmission into the IPTV distribution system. microwave connections and other video feed signals. which may be distributed over a large geographic region. off-air receivers and other types of transmission links. These signals are encoded. An IPTV system has expanded to include multiple regions including local headend locations. After the headend receives. decodes and decrypts these channels. The headend receives.g. off air receivers. separates and converts incoming signals into new formats.5 shows a diagram of a simple headend system. the signals are selected and encoded so they can be retransmitted (or stored) in the IPTV network. The signals are received (selected) and processed using channel decoders. The video sources are scrambled to prevent unauthorized viewing before being sent to the cable distribution system. The incoming signals for headend systems include satellite receivers. This example shows that the programs that will be broadcasted are supplied to encoders produce IP television program streams.g.IPTV Basics
Headend
The headend is the master distribution center of an IPTV system where incoming television signals from video sources (e. Figure 6. decodes. The programs are sent into the IPTV distribution network to distribution points (e. The video sources to the headend typically include satellite signals. Local headends may be connected to regional headends and regional headends may be connected to a super headend.
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. media servers) or directly to end users devices (e. selects and retransmits video programming to the IP distribution network. DBS satellites. This diagram shows that the headend gathers programming sources.g.

5. A decryptor can convert the encrypted information into a form that can be used by the system. IRDs are commonly used to demodulate and decrypt the multi-program transport stream (MPTS) from a satellite antenna. The IRD has a receiver that can select and demodulate a specific channel. decrypt and convert broadcast signals (such as from a satellite system) into a form that can be transmitted or used by other devices. An interface converter may change the format of the media so that it can be used by other devices. The inputs to an IRD (the front end) can include a satellite receiver or a data connection (such as an ATM or IP data connection). The types of processing that an IRD performs can vary from creating analog video signals to creating high definition video digital formats. The outputs of an IRD range from
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. The decoder divides an incoming channel into its component parts.Chapter 6
Figure 6. Headend System
Integrated Receiver Decoder (IRD)
An integrated receiver and decoder is a device that can receive. decode. In headend systems.

Figure 6. Companies that produce IRDs commonly offer variations of IRD (such as analog and digital outputs) that meet the specific needs of the IPTV system operator. Broadcast receivers are used in cable television systems to receive local broadcasted channels so they can be rebroadcasted in the local cable television system.
Figure 6.IPTV Basics
simple video outputs to high-speed IP data connections. Headend Integrated Receiver and Decoder
Off Air Receivers
An off air receiver is a device or assembly that can select.6.6 shows the basic function of an integrated receiver device that is used in an IPTV system to receive satellite broadcasted signals and decode the channels. demodulate and decode a broadcasted radio channel. This example shows that an IRD contains a receiver section that can receive and demodulate the MPTS from the satellite.
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. This IRD can decode and decrypt the MPTS to produce several MPEG digital television channels.

Chapter 6
In some countries (such as the United States). PAL or SECAM) or they may be capable of demodulating and decoding digital television channels (e. A video encoder is a device used to form a single (composite) color signal from a set of component signals. Their destination may be a media server or media hub that redistributes the
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. NTSC.
Transcoders
A transcoder is a device or assembly that enables differently coded transmission systems to be interconnected with little or no loss in functionality. A packet switch is used in an IPTV headend to select and forward packets from television program streams to their destination in the IPTV system. DTT). Off-air receivers may be simple analog television tuners (e. The off-air receiver contain a tuning head that allows it to select (or to be programmed to select) a specific television channel. IPTV operators are required to rebroadcast local television channels on their cable television systems. These “must carry” regulations are government requirements that dictate that a broadcaster or other media service provider must retransmit (carry) or make available to carry a type of program or content. and sends the packet toward its next destination.
Packet Switch
A packet switch is a device in a data transmission network that receives and forwards packets of data. Off-air receivers contain a tuner (receiver). reads its address. An encoder is used whenever a composite output is required from a source (or recording) that is in a component format.g. The packet switch receives the packet of data. demodulator and decoder for analog and/or digital television signals.g. searches in its database for its forwarding address.
Encoders
An encoder is a device that processes one or more input signals into a specified form for transmission and/or storage.

Workflow management for television systems involves the content acquisition. Each asset is given an identification code and descriptive data (metadata) and the licensing usage terms and associated costs are associated with the asset.
Asset Management
Asset management is the process of acquiring.IPTV Basics
packet stream to a group of recipients (viewers watching the same program) or to an individual viewing device (such as a viewer who is watching a video on-demand program). Figure 6. maintaining. Assets are managed by workflow systems. distributing and the elimination of assets. Assets are transferred into short term or long term storage systems that allow the programs to be retrieved when needed. Advertising messages may be inserted into the programs. Schedules (program bookings) are set upto retrieve the assets from storage shortly before they are to be broadcasted to viewers. metadata management. This diagram shows that a workflow management system starts with gathering content and identifying its usage rights. asset storage. When programs are broadcasted. Channel and program playout schedules are created and setup. The descriptive metadata for the programs is then managed and the programs are stored in either online (direct). nearline (short delay) or offline (long term) storage systems. As programs are transferred from storage systems.7 shows some of the common steps that occur in workflow management systems. Assets for television systems are programs or media files. they may be processed and converted into other formats. ad insertion and distribution control. The performance of the system is continually monitored as programs are transmitted `through the distribution systems. content processing. Content assets are acquired or created.
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. playout scheduling. they are converted (encoded) into forms that are suitable for transmission (such as on radio broadcast channels or to mobile telephones).

Content acquisition commonly involves applying a complex set of content licensing requirements. content is ingested (adapted and stored) into the asset management system. Television Workflow Management Systems
Content Acquisition
Content acquisition is the gathering content from networks. The content acquisition system is linked to a billing system to calculate the royalties and other costs for the media. After content is acquired (or during the content transfer). migrated to a playout server or played directly into the transmission chain. Content licensing terms may define the specific type of systems (e.Chapter 6
Figure 6.g. Metadata
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. aggregators and other sources. These licensing terms are included in content distribution agreements. cable. from a satellite downlink or a data connection) and loaded onto initial video servers (ingest servers). the geographic areas the content may be broadcasted (territories). the types of viewers (residential or commercial) and specific usage limitations (such as number of times a program can be broadcasted in a month). Internet or mobile video).7. describing and applying rules to the descriptive portions (metadata) of content assets. Ingesting content is a process for which content is acquired (e. restrictions and associated costs to the content.
Metadata Management
Metadata management is the process of identifying. Once content is ingested it can be edited to add commercials.g.

8 shows the playout scheduling involves selecting programs and assigning playout times. narrative audio clips) and special effects (such as a squeeze back). or other criteria.g. Playout systems are used to set upplaylists that can initiate automatic playout of media during scheduled interviews or alert operators to manually set upand start the playout of media programs (e. text crawls (scrolling text). Metadata normalization is the adjustment of metadata elements into standard terms and formats to allow for more reliable organization. selection and presentation of program descriptive elements. time period. Metadata may be used to create or supplement the electronic programming guide (EPG).g. Examples of secondary events include logo insertion. EPGs can vary from simple program selection to interactive filters that dynamically allow the user to filter through program guides by theme. Primary events are the program that will be broadcasted and secondary events are media items that will be combined or used with the primary event.
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. taps or DVDs). An EPG is an interface (portal) that allows a customer to preview and select from a possible list of available content media. voice over (e. Playout systems are used to select and assign programs (digital assets) to time slots on linear television channels. A playout system is an equipment or application that can initiate.IPTV Basics
descriptions and formats can vary so metadata may be normalized. This diagram shows a playout system that has multiple linear television channels and that events are set upto gather and playout media programs. transferring or streaming of media to users or distributors of the media at a predetermined time schedule or when specific criteria have been met. Playout systems may be capable of selecting primary and secondary events. manage and terminate the gathering. Figure 6.
Playout Scheduling
Playout scheduling is the process of setting up the event times to transfer media or programs to viewers or distributors of the media.

Asset Storage
Asset storage is the maintaining of valuable and identifiable data or media (e. schedule or when specific criteria have been met (such as user registration and payment). television program assets) in media storage devices and systems. Asset storage systems may use a combination of analog and digital storage media and these may be directly or indirectly accessible to the asset management system. broadcasters may use playout automation to reduce the effort (workload) to set upplayout schedules.g.8.
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. Playout automation is the process of using a system that has established rules or procedures that allows for the streaming or transferring media to a user or distributor of the media at a predetermined time. Television Playout Scheduling
Because the number of channels and programs is increasing.Chapter 6
Figure 6.

encoding and/or transcoding. modification or merging of media into other formats. Analog television storage systems may include tape cartridge (magnetic tape) storage. nearline storage. Examples of offline storage systems include storage tapes and removable disks. storage and transfer capabilities. Media in offline storage systems must be located and set upfor connection or transfer to be obtained. Content processing may include graphics processing. and offline storage. online storage. removable and fixed disks and electronic memory. broadcasted) may be moved to nearline storage before it is moved to an online storage system.g. Media may be moved from one type of online storage system to another type of online storage system (such as a disk drive) to another type of online storage (such as electronic memory) that would allow for rapid access and caching. Some of the different types of storage systems include cache storage (high speed immediate access).IPTV Basics
Asset management systems commonly use several types of storage devices that have varying access types. Data or media that is scheduled to be transmitted (e. The requirement to find and/or set upa connection to media or information on a nearline storage system is relatively small. Nearline storage is a device or system that stores data or information that is accessible with some connection set upprocesses and/or delays. Offline storage is a device or system that stores data or information that is not immediately accessible.
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. Caching is a process by which information is moved to a temporary storage area to assist in the processing or future transfer of information to other parts of a processor or system. Asset storage devices are commonly set upin a hierarchical structure to enable the coordination of storage media. Online storage is a device or system that stores data that is directly and immediately accessible by other devices or systems. Online storage types can vary from disk drives to electronic memory modules. Digital storage systems include magnetic tape.
Content Processing
Content processing is adaptation.

Content encoding may include media compression (reducing bandwidth). Ad inserts are typically inserted on a national or geographic basis that is determined by the distribution network. Cue tones can be a simple event signal or they can contain additional information about the event that is about to occur. Ad inserts can be directed to specific users based on the viewer’s profile. Graphics processing may be required to integrate (merge or overlay) graphic images with the underlying programs. transmission coding (adapting for the transmission channel) and channel coding (adding control commands for specific channels).
Ad Insertion
Ad insertion is the process of inserting an advertising message into a media stream such as a television program. For broadcasting systems. Content encoding is the manipulation (coding) of information or data into another form. An example of transcoding is the conversion of MPEG-2 compressed signals into MPEG-4 AVC coded signals.
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. Ad splicers receive cueing messages (get ready) and splice commands (switch now) to identify when and which media programs will be spliced. Transcoding is the conversion of digital signals from one coding format to another. For IP television systems. Cue tones are signals that are embedded within media or sent along with the media that indicates an action or event is about to happen.Chapter 6
A graphics processor is an information processing device that is dedicated for the acquisition. analysis and manipulation of graphics images. An advertising splicer is a device that selects from two or more media program inputs to produce one media output. An example of a cue tone is a signal in a television program that indicates that a time period for a commercial will occur and how long the time period will last.

the splicing of digital media is more complex than the splicing of analog media that has picture information in each frame which allows direct frame to frame splicing.g. going to different audiences to share a single avail. When the incoming media is received by the splicer/remultiplexer. Digital program insertion is the process of splicing media segments or programs together.
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. This diagram shows that the program media is received and a cue tone indicates the beginning of an advertising spot. Through the use of addressable advertising. 30 or 40 seconds each. which may provide access to hundreds of thousands of ads with different time lengths. An ‘avail’ is the time slot within which an advertisement is placed. it is possible for many different advertisements. The resulting media stream with the new ad is sent to the viewers in the distribution system. 20. a commercial). it informs the ad server that an advertising media clip is required. The ad server provides this media to the splicer which splices (attaches) each ad to the appropriate media stream.9 shows how an ad insertion system works in an IPTV network. Figure 6.IPTV Basics
Analog cue tone is an audio sequence (such as DTMF tones) that indicates a time period that will be available (‘avail’) for the insertion of another media program (e. Avail time periods usually are available in standard lengths of 10. Because digital media is typically composed of key frames and difference pictures that compose a group of pictures (GOP).

terrestrial radio broadcast systems (e. A work order is a record that contains information that defines and
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. set upand manage assets.g. Television Ad Splicer
Distribution Control
Distribution control is the processes that are used to route products or service uses to get from the manufacturer or supplier to the customer or end user.9. cable television distribution. VC-1 along with other compressed forms. IPTV broadcasters may have several types of distribution networks including IP streaming. DTT). Asset management systems use work orders to define. multicast (point to multipoint) and unicast (point to point).Chapter 6
Figure 6. mobile video and Internet streaming. Distribution systems use a mix of media encoding formats that can include MPEG. The transmission of media to viewers ranges from broadcast (one to many).

a separate communication session must be established and managed between each user (client) and the broadcast provider (media server).g. creation. IPTV signals are transmitted over a broadband IP network or a network that can transport broadband IP packets (such as an ATM or Ethernet system). IPTV distribution networks may be divided into a core network and an access network. it is desirable to automate the workflow process. popular programming (e. network programming) that is watched by multiple viewers at the same time is copied and redistributed (multicast) locally to the simultaneous viewers. As the number of available programs and channels increases. Several thousand or hundreds of thousands of viewers would require 2 to 4 MByte connections each. television programs) or services. To overcome this bandwidth challenge. Workflow automation is the process of using a system that has established rules or procedures that allows for the acquisition. Multicast service is a one-to-many media delivery process that sends a single message or information transmission that contains a multicast address (code) that is shared by several devices (nodes) in a network. If unicasting is used to provide broadcast services. IPTV systems may use a combination of individual channels (unicasting) or through shared channels (multicasting) in the distribution network. This means that the
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. If each user were connected directly to the headend of the system. The development and management of assets is called workflow. Each device that is part of a multicast group needs to connect to a router (node) in the network that is part of the multicast distribution tree.g. Unicasting is the delivery media or data to only one client per communication session. scheduling or transmission of content assets.
Distribution Network
The distribution network is the part of an IPTV television system that connects the headend of the system (video and media sources) to the customer’s location. the amount of data transmission required at the headend of the system would be substantial.IPTV Basics
quantifies a process that is used in the production of media (e.

Chapter 6
multicast media (such as an IPTV channel) is only sent to the users (viewers) who have requested it. If the program is not available from the regional or central headend. A fiber ring is an optical network of network topology with a connection that provides a complete loop. a regional hub) which may still contain the program. Core networks in IPTV systems are commonly set upas fiber rings and spurs. the program may be requested and obtained from the content provider (e. For users who want to watch a program after it has been removed from a nearby server.10 shows how an IPTV distribution system may use a combination of fiberoptic cable for the core distribution and broadband access for the local connection. A fiber spur is a fiber line that extends the fiber ring into another area for final distribution. IPTV distribution systems commonly locate media servers throughout the distribution network to temporarily store popular television content.g. This means that programs that are stored in media servers located throughout the IPTV distribution network must be deleted after a short time to make storage memory space available for additional programs. drastically reducing the bandwidth requirements. This allows for the supply of popular content (such as sports programs) during and shortly after the program has been broadcasted from local media servers. the signal will
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. The benefit of multicasting is the network infrastructure near the user (e. The core network primarily provides interconnection and transfer between edge networks. a home) only needs to provide one or two channels at once. Media servers can only hold a limited amount of programs.g. The ring topology is used to provide a backup distribution path as traffic to be quickly rerouted in the other direction around the loop in the event of a fiber cut.g.
Core Network
The core network is the central network portion of a communication system. This diagram shows that the multiple television channels at the headend of the IPTV television system are distributed through high-speed fiber cable. Figure 6. their viewing request will be forward up towards a higher level sever (e. The fiber cable is connected in a loop around the local television service areas so that if a break in the optical cable occurs. the movie studio).

The loop is connected (tapped) at regular points by a fiber hub that can distribute the optical signals to local access points.g. wireless broadband (WBB).
Figure 6. set top box) communicates to the system using broadband data channels. powerline carrier (PLC) and optical networks. The types of access networks that may be used by IPTV service providers include digital subscriber line (DSL). IP Television Program Distribution System
Access Network
Access network is a portion of a communication network that allows individual subscribers or devices to connect to the core network. cable television (CATV). the end user device (e.10. For IPTV systems. This example shows that the local access points may contain video servers so that popular content can be redistributed (shared between multiple viewers) or it will be available for viewing at a later time (time shifted television).IPTV Basics
automatically be available from the other part of the loop.
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.

cable modems. asymmetric DSL systems (ADSL) are commonly used. Broadband access systems that may be suitable for IP television systems include digital subscriber line. DSL systems have dedicated wire connections between the systems digital subscriber line access modem (DSLAM) and the user’s DSL modem. Broadband access systems that can provide data transmission rates of over 10 Mbps are called Ultra Broadband systems. unmanaged systems may provide acceptable data transmission rates for quality IP television programs. Because IP television data transmission is primarily from the system to the user (the downlink). the transmission medium is an analog carrier signal (or the combination of many analog carrier signals) that is modulated by the digital information signal. DSL systems have data transmission rates that range from 1 Mbps to over 52 Mpbs.
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. Broadband access systems that are controlled can guarantee the performance (data transmission rates). If the broadband access system has data transmission rates that are several times the required data transmission rates for IP television (2 to 4 Mbps). wireless broadband and powerline data. Although the transmitted information is in digital form. Multiple DSL lines to the same location (multiple pairs of wires) may be combined to provide data transmission rates of over 100 Mbps (bonded DSL).
Digital Subscriber Line (DSL)
Digital subscriber lines transmit high-speed digital information. Broadband access systems that are uncontrolled offer best effort delivery. usually on a copper wire pair. The data transmission rates in DSL systems can be different in the downlink and uplink directions (asymmetric) or they can be the same in both directions (symmetric).Chapter 6
Broadband access systems are networks that can transfer data signals at a rate of 1 Mbps or more. Broadband access systems may be controlled (managed) or uncontrolled (unmanaged) systems.

This example shows that each single IP television user typically requires 3 to 4 Mbps of data transfer. This means that customers who are located close to the DSLAM (may be located at the switching system) can have several set top boxes while IP television customers who are located at longer distances from the DSLAM may only be able to have one IP set top box. the DSL service provider can install DSLAMs at additional locations in their system. There is also a reduction in data transmission rate as the distance from the DSLAM increases. As the distance increases from the DSLAM to the customer. When the data transfer rate is above 5-7 Mbps. For a telephone system operator that uses distance sensitive DSL service. The data transmission required for each IP set top box in the home is approximately 2-4 Mbps.11 shows how the number of simultaneous IP television users per household geographic serving area can vary based on the data transmission capability of the service provider. As the demand for IP television service increases. The further the distance the user is from the DSLAM. the number of set top boxes that can operate decreases. up to 2 IP televisions can be simultaneously used and when the data transmission is between 10 to 14 Mbps. some have different versions with varying capabilities such as higher data transmission rates and longer transmission distances. up to 3 IP televisions can be simultaneously used. symmetric digital subscriber line (SDSL) and very high bit rate digital subscriber line (VDSL). this example shows that the service provided will be limited to providing service to a single IP television when the data transfer rates are limited to 3-4 Mbps.IPTV Basics
There are several types of DSL systems including asymmetric digital subscriber line (ADSL). the maximum distance of DSL transmission is limited. In 2005.
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. Because the telephone wires that DSL uses do not transfer high-frequency signals very well (high signal loss at higher frequencies). the typical maximum distance that DSL systems operated is 3 to 5 miles from the DSLAM. Figure 6. the lower the data transmission rate. Of the different types of DSL.

11. some of the channels (usually the higher frequency channels) are converted from analog signals to digital video and data signals.
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.Chapter 6
Figure 6. IP Television DSL Carrier Serving Area
Cable Modem
A cable modem is a communication device that modulates and demodulates (MoDem) data signals through a cable television system. Converting a television channel to cable modem provides data transmission rates of 30-40 Mbps per television channel from the system to the user and 2-4 Mbps from the user to the cable system. To provide cable modem service. Cable modems operate over the same frequency band as a television channel (6 MHz for NTSC and 8 MHz for PAL). Cable television systems have traditionally been used to transfer analog television channels from the media source (cable company headend) to end users (televisions). Cable modem users on a cable television system typically share a data channel. Cable modems select and decode high data-rate signals on the cable television system (CATV) into digital signals that are designated for a specific user. A single analog television channel can be converted to approximately 6 digital television channels. Each coaxial cable is capable of carrying over 100 channels.

Each of the upper digital channels can transfer 30 to 40 Mbps and each of the lower digital channels can transfer data at approximately 2 Mbps.IPTV Basics
DOCSIS is a standard used by cable television systems for providing Internet data services to users. Cable Modem System
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. medium access control (MAC).12. This diagram shows that the cable television operator’s headend system contains both analog and digital television channel transmitters that are connected to customers through the distribution lines. It details most aspects of data over cable networks including physical layer (modulation types and data rates). The cable operator has replaced its one-way distribution amplifiers with precision (lin-
Figure 6. distribution lines with amplifiers. and cable modems that connect to customers’ computers. Some of the upper television RF channels are used for digital broadcast channels that transmit data to customers and the lower frequency channels are used to transmit digital information from the customer to the cable operator. Figure 6. services and security. The distribution lines (fiber and/or coaxial cable) carry over 100 television RF channels.12 shows a basic cable modem system that consists of a headend (television receivers and cable modem system). The DOCSIS standard was developed primarily by equipment manufacturers and CATV operators.

Wireless broadband often refers to data transmission rates of 1 Mbps or higher. the cost of wireless system bandwidth has been traditionally higher than wired systems. 3G mobile communication. if the data transmission rate of each satellite channel is divided for number of viewers. Some satellite systems use multiple beam transmission (spot beams) which can dramatically increase the available data transmission rates for each user. fixed microwave (MMDS/LMDS).
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. While the installation time for wireless systems is relatively short. wireless LAN (WLAN) and WiMax. This is because wireless systems generally cannot multiply their bandwidth by adding more wire or lines. Fixed wireless systems generally have higher data transmission rates than mobile wireless systems. Satellite systems cover a very wide geographic area and they are well suited for one to many communications. data and/or voice signals directly to end-users.Chapter 6
ear) high frequency bi-directional (two-way) amplifiers. Another typical tradeoff for a wireless system is higher mobility results in lower data transmission rates. While this system works well for simultaneous viewers. The radio transmission from the digital broadcast satellite systems can provide data transmission at several hundred Mbps providing hundreds of digital video channels. Each high-speed Internet customer has a cable modem that can communicate with the cable modem termination system (CMTS) modem at the on-demand of the system where the CMTS system is connected to the Internet. Some of the available systems that can offer wireless broadband services include satellite systems. the individual data rates will be relatively low (in the kbps).
Wireless Broadband
Wireless broadband is the transfer of high-speed data communications via a wireless connection. Wireless cable provides video programming from a central location directly to homes via a small antenna that is mounted on the side of the house. Wireless broadband is commonly given the name “Wireless Cable” when it is used to deliver video.

much of the live digital video transmission for mobile communication systems in 2005 had data transmission rates of approximately 144 kbps. After many communication proposals were reviewed. However.
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. Optionally. As a result. global roaming. MMDS service evolved from radio channels that were originally authorized for educational video distribution purposes. MMDS is a wireless cable service that is used to provide a series of channel groups.IPTV Basics
There are two basic types of wireless cable systems. two global systems are emerging. In the United States. The 802. The 3rd generation wireless requirements are defined in the International Mobile Telecommunications “IMT-2000” project developed by the International Telecommunication Union (ITU). consisting of channels specifically allocated for wireless cable (the “commercial” channels).1 to 2.5 to 2.69 GHz. MMDS video broadcast systems have been in service since the early 1990’s providing up to 33 channels of analog television over a frequency range from 2. wideband code division multiple access (WCDMA) and CDMA2000/EVDO.69 band. A wireless local area network (WLAN) is a wireless communication system that allows computers and workstations to communicate data with each other using radio waves as the transmission medium. Internet Protocol (IP)-based services.11 industry standard and its various revisions are a particular form of Wireless LAN. there are 31 “response channels” available near the upper end of the 2. The IMT-2000 project that defined requirements for high-speed data transmission. These response channels were originally intended to transmit a voice channel from a classroom to a remote instructor. The maximum data transmission rates for 3G mobile communication systems can be over to 2 Mbps. and multimedia communications. Multichannel Multipoint Distribution Service (MMDS) and Local Multichannel Distribution Service (LMDS). the highest data transmission rates only can be achieved when the user is located close to the radio tower (cell site) and their interference levels (signals from other towers and users) are low.

This standard evolved through new modulation to produce 802. To help ensure Wi-Fi products perform correctly and are interoperable with each other.4 GHz and provided data transmission rates up to 11 Mbps. and maximum data transmission rates.Chapter 6
802. Wireless LANs can be connected to a wired LAN as an extension to the system or it can be operated independently to provide the data connections between all the computers within a temporary (“ad-hoc”) network. the Wi-Fi Alliance was created in 1999.11 WLAN is commonly referred to as “Wi-Fi” (wireless fidelity). Data rates for WLAN systems typically vary from 1 Mbps to more than 50 Mbps.11b that operated at 2. Wireless LAN configurations range from temporary independent connections between two computers to managed data communication networks that interconnect to other data networks (such as the Internet). This diagram shows that the original 802. This diagram also shows
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.13 shows how 802. Figure 6. There are several different versions of 802. and hotels. type of wireless access. airports. but without the physical constraints of the wire itself. Examples of hot spots include wireless LAN (WLAN) access points in coffee shops. Hot spots are geographic regions or service access points that have a higher than average amount of usage. The key differences include frequency band. Wi-Fi® is a registered trademark of the Wi-Fi Alliance and the indication that the product is Wi-Fi Certified™ indicates products have been tested and should be interoperable with other products regardless of who manufactured the product.11 LAN systems have evolved over time.11 wireless LAN.4 GHz. WLANs can be used in both indoor and outdoor environments.11 specification offered 1 or 2 Mbps data transmission rates and operated at 2. Wireless LANs can provide almost all the functionality and high data-transmission rates offered by wired LANs.11 WLAN systems that have evolved over time and some (not all) of these versions are compatible with other versions of 802. The Wi-Fi Alliance is a nonprofit organization that certifies products conform to the industry specification and interoperates with each other. Wireless LAN systems may be used to provide service to visiting users in specific areas (called “hot spots”).

and Internet Protocol (IP) and it has the capability to differentiate and provide differing levels of quality of service (QoS).
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. Like the short range 802.IPTV Basics
that a new 802.11b systems.16 systems primarily defines the physical and media access control (MAC) layers.
Figure 6. Wireless LAN Evolution
WiMax is a name for the IEEE 802. Ethernet.4 GHz range.7 GHz.16A point to multipoint broadband wireless industry specification that provides up to 268 Mbps data transmission rate in either direction with a maximum transmission range of approximately 3-10 km [1]. the 802.11a system was developed that provides data transmission rates up to 54 Mbps at 5. To help provide high-speed data transmission rates and provide backward compatibility to 802.13.11g systems was developed that offers 54 Mbps data transmission in the 2.11 and 802. the 802. The system was designed to integrate well with other protocols including ATM. The WiMax system is primarily defined to operate in either the 10 GHz to 66 GHz bands or the 2 GHz to 11 GHz bands.11 wireless local area network (WLAN) specification.

In this example.. Internet). This diagram shows that the major component of a WiMax system include subscriber station (SS).g. PSTN) and television (e.g.14 shows the key components of a WiMax system. When used for television services.14. IPTV). An antenna and receiver (subscriber station) in the home or business converts the microwave radio signals into broadband data signals for distribution in the home. a base station (BS) and interconnection gateways to datacom (e.
Figure 6. WiMax System
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. When WiMax is used for broadband data. the WiMax system also connects the Internet through a gateway to the Internet.g. the WiMax system converts broadcast signals to a data format (such as IPTV) for distribution to IP set top boxes. a WiMax system is being used to provide television and broadband data communication services. This example also shows that the WiMax system can reach distances of up to 50 km. telecom (e.Chapter 6
Figure 6.

Powerline transformers typically block high frequency data signals so data routers or bridges are typically installed near transformers.IPTV Basics
Power Line Carrier (PLC)
Power line carrier is the simultaneous sending of a carrier wave information signal (typically a data signal) on electrical power lines to transfer information. A power line carrier signal is above the standard 60 Hz or 50 Hz frequency that transfers the electrical energy. There are often many homes per transformer (over 1. the high voltage portion of the transmission system is modified to include communication transceivers that can withstand the high voltages while coupling/transferring their information to other receivers that are connected to the high voltage
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. Multiple transmission channels can be combined to provide highspeed data transmission rates. each power line transmission carrier signal is handled independently. Utility companies typically set updata nodes near transformers and each data node provides signals to homes that are connected to the transformers. Power line carrier systems used in wide area distribution transfer signals from a data node located in the power system grid to a data termination box located in the home. some of the signal energy leak from the power lines and some undesired signals are received into the power lines from outside sources (such as AM radio stations). In this example. Because power lines were not designed for low and medium frequency signals. If the signal energy is lost or if other signals interfere with one frequency. Power line carrier systems typically use multiple transmission channels (low and medium frequencies) to communicate between the power system data node and the data termination box.000 homes) in developing countries and a lesser number of homes per transformer (less then 12 homes) in developed countries. Because the interference is typically different for each frequency. Figure 6. one or several other transmission channel frequencies can be unused.15 shows three types of communication systems that use an electrical power distribution system to simultaneously carry information signals along with electrical power signals.

Ethernet) communication. Optical access networks may use fiber to con-
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Figure 6. This example also shows a power line distribution system that locates a communication node (radio or fiber hub) near a transformer and provides a data signal to homes connected to a transformer.g. Powerline Broadband Data Transmission
Optical Access Network
An optical access network is a portion of a communication network that allows individual subscribers or devices to connect to the core network through optical connections.15. This system could allow customers to obtain Internet access or digital telephone service by plugging the computer or special telephone into a standard power socket. The diagram also shows how a consumer may use the electrical wiring in their home as a distribution system for data (e. This type of communication could be used to monitor and control power distribution equipment such as relays and transformers or as a highspeed data backbone transmission connection using fiber.Chapter 6
lines.

For a fiber to the home (FTTH) system.16. The ONT functions as the optical signal converter and the network end termination point. the optical signal travels to an optical network termination (ONT) that is located in the customer’s premises.16 shows an example of an optical access network.
Figure 6. the optical signal travels to an optical network unit (ONU) located in a geographic region close to the customer (their neighborhood).IPTV Basics
nect to a node (distribution point) in a neighborhood. The ONU converts the optical signal into a format that is sent to a network termination (NT) at the customer’s premises. Optical Access Network
Premises Distribution
A premises distribution network is the equipment and software that is used to transfer data and other media in a customer’s facility. home or personal
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. Figure 6. For a fiber to the neighborhood (FTTN) system. This diagram shows that the telecommunications network is converted to a format suitable for an optical access network by an optical line termination (OLT). the optical signal is sent to an ONU located at the curb near the customer’s premises. For a fiber to the curb (FTTC) system. to a node outside a home or to a optical network termination (ONT) that is located in the home or business.

Wireless local area network (WLAN) systems allow computers and workstations to communicate with each other using radio propagation as the transmission medium. Powerline. Each of the applications that operate through a PDN can have different communication requirements that typically include a maximum data transmission rate. The wireless LAN can be connected to an existing wired LAN as an extension. Coaxial and Phoneline Data. several new WLAN standards were created to enable and ensure different types of quality of service (QoS) over WLAN. A power line carrier signal is transmitted above
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. Transmission medium types for premises distribution include wired Ethernet (data cable). Wireless LAN data transmission rates vary from 2 Mbps to over 54 Mbps and higher data transmission rates are possible through the use of channel bonding. packet delay and jitter and error tolerance. Wireless LAN. WLAN networks were not designed specifically for multimedia. The PDN system may manage these connections using a mix of protocols that can define and manage quality of service (QoS). In the mid 2000s. or it can form the basis of a new network. A PDN is used to connect terminals (computers) to other networks and to wide area network connections. Wired LAN systems use cables to connect routers and communication devices. Power line carrier systems allow signals to be simultaneously transmitted on electrical power lines. While wired Ethernet systems offer high data throughput and reliability. powerline. WiFi television distribution is important because it is an easy and efficient way to get digital multimedia information where you need it without adding new wires. wireless. Wired LAN data transmission rates vary from 10 Mbps to more than 1 Gbps. many homes do not have dedicated wiring installed for Ethernet LAN networks and for the homes that do have data networks. continuous or bursty transmission. the outlets are often located near computers rather than near televisions. phoneline and coaxial cables. simple command and control systems to high-speed multimedia networks along with the ability to transfer a variety of media types that have different transmission and management requirements. PDN networking systems have transitioned from low speed data. Some of the common types of PDN are wired Ethernet. These cables can be composed of twisted pairs of wires or optical fibers.Chapter 6
area.

Telephone wiring premises distribution systems transfer user information over existing telephone lines in a home or building. they are set upas a tree distribution system. When coax systems are set upas simple distribution systems. Coaxial cable premises distribution systems transfer user information over coaxial television lines in a home or building. DSL). Because telephone lines may contain analog voice signals and data signals (e. Older (legacy) power line communication systems had challenges with wiring systems that used two or more phases of electrical power. digital media adapters (DMAs) and other media devices are already connected to power outlets already installed in a home or small businesses. The broadband modem is connected to a router that can distribute the media signals to for-
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. set-top boxes. Coaxial cable data transmission rates vary from 1 Mbps to over 1 Gbps and many homes have existing cable television networks and the outlets which are located near video accessory and television viewing points. Today. Power line premises distribution for television is important because televisions.g. When coaxial systems are set upas data networks. data signals at high frequencies (above 860 MHz) are combined with broadcast signals over the same coaxial lines. There are typically several telephone line outlets installed in a home and they may be located near television viewing points. Figure 6. most of these impairments no longer are an impediment to performance and some powerline data systems have data transmission rates of over 200 Mbps. The root of the tree is usually at the entrance point to the home or building.17 shows the common types of premises distribution systems that can be used for IP television systems. premises distribution on telephone lines uses frequency bands above 1 MHz to avoid interference with existing telephone line signals. Coaxial distribution systems may simply distribute (split) the signal to other televisions in the home or they may be more sophisticated home data networks.IPTV Basics
the standard 60 Hz power line power frequency (50 Hz in Europe). Telephone data transmission rates vary from 1 Mbps to over 300 Mbps. making it easy to connect television-viewing devices. with the benefit of modern signal processing techniques and algorithms. This diagram shows that an IP television signal arrives at the premises at a broadband modem. The tree may divide several times as it progresses from the root to each television outlet through the use of signal splitters.

telephone lines.Chapter 6
ward data packets to different devices within the home such as IP televisions.
Figure 6. This example shows that routers may be able to forward packets through power lines.17. coaxial lines. IPTV Television Premises Distribution
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. data cables or even via wireless signals to adapters that receive the packets and recreate them into a form the IP television can use.

This example shows that routers may be able to forward packets
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. PDN networking systems have transitioned from low speed data. packet delay. PDN systems may use wired Ethernet. home or personal area. continuous or bursty transmission.Chapter 7
Premises Distribution Networks (PDN)
A premises distribution network is the equipment and software that is used to transfer data and other media in a customer’s facility. Coaxial or Phoneline connections. Premises distribution systems have evolved to include the ability to transfer a variety of media types that have different transmission and management requirements. Each of the applications that operate through a PDN can have different communication requirements which typically includes a maximum data transmission rate. Figure 7. simple command and control systems to high-speed multimedia networks. The PDN system may manage these connections using a mix of protocols that can define and manage quality of service (QoS). jitter and error tolerance.1 shows the common types of premises distribution systems that can be used for IP television systems. Powerline. A PDN is used for media devices such as digital televisions. computers and audio visual equipment to each other and to other networks through the use of wide area network connections. The broadband modem is connected to a router that can distribute the media signals to forward data packets to different devices within the home such as IP televisions. This diagram shows that an IP television signal arrives at the premises at a broadband modem. Wireless LAN.

Figure 7.g. data cables or even via wireless signals to adapters that receive the packets and recreate them into a form the IP television can use. telephone lines.
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. data and digital video) through a communication network (such as a home network). digital audio. coaxial lines. media players and other media sources and players to each other and to send and receive media from wide area network connections.1.IPTV Basics
through power lines. Premises Distribution Systems
Home Multimedia Service Needs
Multimedia networking is the process of transferring multiple forms of media (e. Multimedia networking is used to connect computers.

The typical types of applications that will be used in the home include telephone. and/or radio signals to transmit sound to remote locations.
Telephone
Telephony is the use of electrical. television. the amount of data transmission for Internet connections continues to increase as rich media sources (video streaming) increase. Some transmission errors are acceptable. the term telephony means interactive communications over a distance. Home telephone usage is typically is less than 1 hour and the usage time (call duration) only lasts for a few minutes.Chapter 7
The communication requirements for multimedia networks in the home is based on the applications that are used in the home along with how much and the times that the applications and services will be used. Internet access can be used for web browsing or data transfer applications. In general. optical. The communication must be real time with minimal transmission delays.
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. Generally. Internet communication tends to require high-speed data transmission in short bursts.
Internet Access
Internet access is the ability for a user or device to connect to the Internet. interactive video and media streaming. telephony has related to the telecommunications infrastructure designed and built by private or government-operated telephone companies. Uncompressed digital telephone signals have a data transmission of approximately 90 kbps. Digital telephone systems (such as Internet telephones) may use a PDN to connect within a home. Traditionally. Short delays are acceptable and transmission errors are usually automatically overcome by Internet protocols. Internet access.

Interactive video services such as video conferencing requires a mid-level amount of data transmission (approximately 200kbps) for medium periods of time (minutes to hours). For some types of digital compression such as MPEG-2.g.g.
Interactive Video
Interactive video services are processes that allow users to interactively provide and receive audio and/or visual information. Although the amount of data transmission for these may be low. The interactive parts range from simple text messages to the simultaneous transfer of large data or media files. they may be used for long durations. even with small amounts of transmission errors (0. home theater) systems.IPTV Basics
Television
A television service is the transmission of television program material (typically video combined with audio).g. Digital television signals require highspeed data transmission rates (2-20 Mbps) that are used for several hours per day. High definition television channels are becoming more available which is likely to result in an increase in the required bandwidth for television signals. A single home can have multiple televisions which require multiple simultaneous data streams.1%) can result in television signals that are unwatchable. double or triple hops)
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. Television viewing often occurs at the same time (e. The data transmission requirements for home media networks may be increased as a result of multiple connection paths (e. evening hours).
Media Streaming
Media streaming applications include security camera connections or music distribution (e.

Double hop connections through a home media network can use up to two times as much data transmission capacity. This table also shows that the highest consumption of bandwidth occurs from television channels. This table shows that some devices may require connections through a gateway to other networks (such as to the Internet or to television systems). Show looking is the rapid browsing through a media program (such as a video) by dragging the media position indicator through a portion or over the entire length of a media program (fast slide). especially when simultaneous HDTV channels are access on multiple television sets. Trick mode commands enable remote control features for the playout of media. Figure 7. Trick mode is a media player function that allows for variations in the presentation of media. Fast slide is the rapid acceleration of playing (presenting) media (such as video) through the rapid movement (dragging) of a position indicator on a media slide control. A double hop is a transmission path that is routed through a communication network where it takes two connection paths to reach its destination rather than through a single direct path.Chapter 7
and as a result of playback modes that can require multiple streams (such as trick modes). rewind and pause.
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. During trick play mode. additional streams may be created.2 shows some of the types of communication devices used in a home and their estimated data transmission requirements. Examples of trick mode are fast forward. This table suggests that a total home media capacity of 70 Mbps to 100 Mbps is required to simultaneously provide for all devices within a home and that a residential gateway have broadband capability of 50+ Mbps. Some of the trick mode features that may increase data transmission requirements include fast sliding and slow looking.

cost and installation. quality of service (QoS). Premises distribution systems typically coexist with one or more types of systems including wireless LAN. security. data rates. Home Audio/Visual and others. Home Multimedia Bandwidth Requirements
Home Multimedia System Needs
The requirements for home multimedia systems vary depending on the needs of the viewers.
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. CATV. Some of the general factors that are considered when selecting a home multimedia networking system include co-existence.IPTV Basics
Figure 7. no new wiring requirements. The PDN system may share the same medium (cables and/or radio waves). the needs of the operator and existing home network systems. Satellite.2.
Co-Existence
Co-existence is the ability of a device or system to operate near or with another device and/or system.

frequency range) is used by one system and another segment (e. sequence. While there are several different protocol languages used for PDN services.
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. Protocols for distribution services (such as RTP) simply ride on top (are encapsulated) into the data packets that
No New Wires
“No New Wires” is a concept that can be used when adding additional communication capabilities in a home or building without adding any new wireless.
Intersystem Interference
Intersystem interference is the interaction of signals or data in one system with signals or data in another system where the interaction results in the performance degradation or unwanted changes in the operation of either system. Intersystem interference may occur between systems that are physically connected or it may occur by signal leakage.
Protocols
Protocols are the languages. and procedures that perform functions used to send control messages and coordinate the transfer of data.g. it may result in distortion or reduced transmission capacity. PDN systems may experience or cause interference with other systems that may be located at adjacent locations (e. processes. the underlying processes are commonly based on Ethernet and IP protocols. The NNW concept does allow for the use of existing wires as part of the new communication system. Interference between wired systems may be reduced or eliminated by the installation of a point of entry (POE) filter. When interference occurs.Chapter 7
To co-exist. and error checking used on a network or computing system. timing. different frequency range) is used by the PDN system. A POE filter is a device (analog or digital) that is designed to allow or block specific signals from entering or leaving a building or facility (at the point of entry). these systems may use segmentation of medium where a portion of the medium (e. neighbors home).g. Protocols define the format.g.

moving from MPEG-2 to MPEG-4) but it is increased by the addition of new applications (media portability and media conversion). Acceptable error rates for video distribution is a packet error rate (PER) of 10^-6 and a bit error rate (BER) of 10^-9 [1]. Error rate may be expressed in the number of bits that are received in error of the number of blocks of data (packets) that are lost over a period of time. Some of the important QoS characteristics for IPTV PDN systems include error rates. Peak when multiple users select options that increate bandwidth such as trick play or rapid channel changing.
Quality of Service (QoS)
Quality of service is one or more measurement of desired performance and priorities of a communications system.g. These features if performed simultaneously by all users in the system could increase the data transmission requirements by 1. transmission delay and jitter.IPTV Basics
Data Rates
Data rate is the amount of information that is transferred over a transmission medium over a specific period of time.5x to 2x. The average data transmission rates is decreased as a result or improved media compression capability (e. The required data transmission rates for home media networks can be characterized by average and peak requirements.
Error Rates
Error rate is a ratio between the amount of information received in error as compared to the total amount of information that is received over a period of time. Some digital video formats (such as MPEG-2) are more sensitive to packet error rates (burst errors) than packet errors.
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.

channel coding delays. cable or optical fiber. queuing delays waiting for available transmission channel time slots. theft or compromise of its resources from unwanted people or events.
Jitter
Jitter is a small. system or service to maintain its desired well being or operation without damage. and channel decoding delays.g.
Home Coverage
Home coverage is the available area (for wireless) or number of outlets (for wired systems) over which the signal strength of a premises distribution network is sufficient to transmit and receive information. transmission line or network) to its exit of the system.
Security
Security is the ability of a person. Common causes of transmission delay include transmission time through a transmission line (less than the speed of light). The overall transmission delay for video signals is an issue for real-time communication (e. Digital video and audio is generally more sensitive to jitter rather than to overall transmission delay. video conferencing) but not much of an issue for broadcast television or on-demand services.
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. Jitter can cause packets to be received out of sequence and miss their presentation window.Chapter 7
Transmission Delay
Transmission delay is the time that is required for transmission of a signal or packet of data from entry into a transmission system (e. rapid variation in arrival time of a substantially periodic pulse waveform resulting typically from fluctuations in the wave speed (or delay time) in the transmission medium such as wire. Security for IPTV home multimedia distribution systems includes privacy and rights management. media or data. switching delays.g.

license or franchise fees. Rights management systems are typically incorporated or integrated with other systems such as content management system. While it is possible for customers to self-install premises distribution systems. transaction and service support costs. identity validation (authentication).” Most PDN systems have the capability of encrypting media so other devices or neighboring systems cannot decode.
Rights Management
Rights management is a process of organization. corresponding to a moderate amount of effort on the part of the eavesdropper to understand the private communication. and royalty management.
Cost
Cost is the fees our resources that are required to produce or provide a product or service. marketing.
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. access control and assignment of authorized uses (rights) of content. and media protection (encryption). service authorization.IPTV Basics
Privacy
Privacy is a level of protection that is minimal. in the initial launch phase of IPTV. billing systems. many carriers have chosen to have their workers or contractors to install the equipment to ensure that both the PDN and IPTV signals are operating correctly. When the equipment has passed operational and performance tests installation may be complete. Rights management may involve the control of physical access to information. but not so good as the better levels designated by the words “secret” or “secure.
Installation
Installation is the locating and configuration of equipment and/or wiring either inside or outside of buildings or facilities. PDN costs can include equipment.

Many PDN systems are designed for plug and play where the devices use self discovery.Chapter 7
Peer to Peer Operation
Peer to peer distribution is the process of directly transferring information. These technologies include adaptive mod-
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. services or products between users or devices that operate on the same hierarchical level (usage types that have similar characteristics). Self discovery may involve finding devices within a system that can provide it’s the identification address. remediation may involve the dispatching of a qualified technician or field service representative to validate.
Remote Diagnostics
Remote diagnostics is a process and/or a program that is built into a device or network component that allows users or devices from remote locations to access information or control operations that can be used to discover the functionality or performance of a device or system connection. Self discovery is the processes used to request and receive information that is necessary for a device to begin operating.
Home Networking Technologies
Home networking systems use key technologies to allow them to reliably provide broadband transmission. and services of other devices.
Upgradeable
Upgradability is the ability of a device or systems to be modified. changed or use newer components and/or as technology innovations become available. For PDN systems.
Remediation
Remediation is the correction of a condition or problem. name. PDN systems may be upgradeable through the use of software downloads. configure or correct faulty installations.

synchronized transmission. interference or data transmission rate). For wired PDN systems.g. PDN systems typically share transmission resources (such as a power line) and the characteristics of these transmission lines can dramatically change (e. power level control and channel bonding. For some PDN systems. there can be many connection paths and some of these connection paths may not be properly installed or terminated which can result in signal reflections. There can also be changes in the PDN systems that occur from the installation.
Adaptive Modulation
Adaptive modulation is the process of dynamically adjusting the modulation type of a communication channel based on specific criteria (e. Adaptive modulation allows a transmission system to change or adapt as the transmission characteristics change. Adaptive modulation allows the PDN transmission system to adapt to the new conditions that occur such as slowing the transmission rate when interference occurs and to return to a more efficient transmission system when the characteristics of the transmission line changes again. interference avoidance.IPTV Basics
ulation. These endpoints that are not properly terminated can cause signal reflections and the signal reflections can cause signal distortion. control or removal devices or configurations. light switch).g.
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.
Echo Control
Echo control is the processes that are used to identify echoes to transmitted signals and the processes that are used to remove the distortions caused by the signal echoes. the characteristics of the transmission line can dramatically change over short periods of time.

The distortion caused by echoed signals in PDN systems can usually be removed through the use of echo canceling. Devices request transmission resources (e.g. The use of synchronized transmission reserves transmission resources (bandwidth reservation) for time critical information such as television or telephone media. reserved bandwidth). it reserves the bandwidth in messages it periodically sends throughout the PDN. When the characteristics of the mediums are different (impedance). Echoed signals may be received at other devices and these cause distortion in their received signals. The master controller coordinates transmissions within the PDN. If the master unit has the bandwidth available and it determines the requesting device is authorized to use the service.Chapter 7
Signal reflection is the sharp changing of the direction of a transmitted signal as it passes from one transmission medium to another (transmission channel or device). Echo cancellation is a process of extracting an original transmitted signal from the received signal that contains one or more delayed signals (copies of the original signal). PDN systems may use one of the devices that are connected to the PDN as a master controller. Some of the energy of the forward signal (incident signal) is redirected (reflected) back towards the signal source.
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.
Synchronized Transmission
Synchronized transmission is the transferring of information during a time period that is previously defined (time synchronized) or transmission occurs after another event (such as a synchronization message). Echo canceling may be removed by performing via advanced signal analysis and filtering. a reflected signal will be generated. The use of synchronized transmission provided for reduced transmission delays (limited latency) minimizes jitter and provides for low error rates. Synchronized transmission is used to ensure (guarantee) that certain types of information will be provided at specific times when it is required.

After a PDN device has decoded the MAP message and has determined that its time to transmit has occurred. Power control is typically accomplished by sensing the received signal strength level and relaying power control messages between the receiver and transmitter that indicates or instructs the transmitter to increase or decrease it’s output power level. it can begin transmitting without coordinating with other device (contention free). devices that operate within the same frequency band and within the same physical area can detect the presence of each other and adjust their communication system to reduce the amount of overlap (interference) caused by each other. In general. the master unit periodically sends media access plan (MAP) messages that has a list of devices and their assigned transmission schedules and priorities for media transmission. the closer the transmitter is located to the receiver. the lower the amount of power level that needs to be transmitted. By using interference avoidance.
Power Level Control
Power level control is a process of adjusting the power level of a transmitter on a communication link to minimize the amount of energy that is transmitted while ensuring enough signal level is transmitted so a desired reception quality can be achieved.
Interference Avoidance
Interference avoidance is a process that adapts the access channel sharing method so that the transmission does not occur on specific frequency bandwidths. This reduced level of interference increases the amount of successful transmissions therefore increasing the overall efficiency and increased overall data transmission rate.IPTV Basics
To perform synchronized transmission.
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Chapter 7
Channel Bonding
Channel bonding is the process of combining two or more communication channels to form a new communication channel that can use and manage the combined capacity of the bonded transmission channels. Channel bonding can be used on Wireless PDN systems to increase the overall data transmission rate and to increase the reliability of transmission during interference conditions.
Figure 7. the bonding protocol is used to monitor and manage the bonded connection. This diagram shows how two transmission channels can be combined using a bonding protocol.3. Once the bonded session has been setup. Figure 7.3 shows how multiple transmission channels can be bonded together to produce a single channel with higher data transmission rates. Channel Bonding
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. This diagram shows that a bonded session is requested and negotiated on a single communication channel.

Category 2 cable is UTP cable that can be used for transmission speed up to 4Mbps. A data cable that is used for wired LAN networks is classified by the amount of data it can carry in by the Electronics Industry Association/Telecommunications Industry Association EIA/TIA 586 cabling standard. In general. phoneline and coaxial cables. Wired LAN data transmission rates vary from 10 Mbps to more than 1 Gbps. Wired LAN systems are typically installed as a star network. These cables can be composed of twisted pairs of wires or optical fibers. Category 4 UTP cable can transmit up to 16Mbps and is commonly used for Token Ring networks. the higher the maximum data transmission rate and the higher the category rating of the LAN cable. powerline. LAN wiring is not a commonly installed in many homes and when LAN wiring is installed. wireless. LAN connection outlets are unlikely to be located near television viewing points.
Wired LAN
Wired LAN systems use cables to connect routers and communication devices. category 1 rated cable is unshielded twisted-pair (UTP) telephone cable (not suitable for high-speed data transmissions). Category 5 cable is rated for data trans-
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. The higher the number of twists. The star point (the center of thee network) is usually a router or hub that is located near a broadband modem. Category 3 UTP cable can be used at data transmission speeds of 10Mbps. When wired LAN systems use twisted cable.IPTV Basics
Transmission Types
Transmission medium types for premises distribution include wired Ethernet (data cable). the data transmission rate (cable rating) is based on the number of twists in the cable.

Category 5E (enhanced) has the same frequency range as Category 5 with a lower amount of signal transfer (crosstalk) so it can be used for 1 Gbps Ethernet systems. manufacturing floors.4 shows how an in-home Wi-Fi system can be used for IP Television (IPTV) premises (home) distribution. The broadband modem is connected to a wireless access point (AP) that retransmits the broadband data to different devices through the home including a laptop computer. Figure 7. or it can form the basis of a new network. Some consumers have refused to add new IPTV services due to rewiring or having to retrofit their homes to support it. Wi-Fi television and an IP set top box (IP STB) that has a builtin Wi-Fi receiver. The wireless LAN can be connected to an existing wired LAN as an extension.
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. This diagram shows that a broadband modem is installed in the home that has WLAN with premises distribution capability.
Wireless
A wireless local area network (WLAN) allows computers and workstations to communicate with each other using radio propagation as the transmission medium. This example shows that the broadband modem is located at a point that is relatively far from other devices in the home. While adaptable to both indoor and outdoor environments.Chapter 7
mission speeds up to 100Mbps. wireless LANs are especially suited to indoor locations such as office buildings. Wi-Fi distribution is important because it is an easy and efficient way to get digital multimedia information where you need it without adding new wires. Wi-Fi distribution of IPTV streams from broadband providers is the use of unlicensed radio frequencies to distribute multimedia signals to IP-enabled receiving devices in a home or nearby location. Category 6 cable has a frequency rating of 250 MHz. hospitals and universities.

Figure 7.5 shows the different product groups of 802. Some versions of the 802.11 WLAN over time as new more advanced modulation technologies are used. The first systems could only transmit at 1 Mbps.IPTV Basics
Figure 7.11 systems and how the data transmission rates have increased in the 802. Wireless IPTV Distribution
Wireless LAN premises distribution systems transfer user information over a WLAN system in a home or building. The current evolution of 802. Multimedia signals such as television and music are converted into WLAN (Ethernet) packet data format and distributed through the home or business by wireless signals.11A and 802.
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.11 WLAN specifications include the ability to apply a quality of service (QoS) to the distributed signals giving priority to ensure that time sensitive information (such as video and audio) can get through and non-time sensitive information (such as web browsing).11G allows for data transmission rates of up to 54 Mbps. Higher data transmission rates are possible through the use of channel bonding. Wireless LAN data transmission rates vary from 2 Mbps to over 54 Mbps.4.

Power Line
Power line carrier is a signal that can be simultaneously transmitted on electrical power lines. several new WLAN standards were created to enable and ensure different types of quality of service (QoS) over WLAN. The amount of data that could be transferred was limited and the applications typically consisted of controlling devices such as light switches and outlets. Some of the early home automation systems include: X-10. In the mid 2000s. CeBus and LONworks. Power line communication signals travel from their entry onto the home power line system (typically from a powerline-enabled broadband modem such as WiMAX. cable modem or a fiber optic Network Interface
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. Wireless LAN Standards
WLAN networks were not designed specifically for multimedia.Chapter 7
Figure 7. A power line carrier signal is transmitted above the standard 60 Hz powerline power frequency (50 Hz in Europe).5. The power line communication systems developed in the 1970s used relatively low frequencies such as 450 kHz to transfer data on power lines. DSL.

a dryer outlet). halogen lamps and dimmer switches. much of the coverage challenge was due to the difficulty of powerline communication signals to propagate on electrical powerlines that are on different phases. Today. The power line communications coverage within a home is expressed as a rate of speed over a certain percentage of outlets. cross phase
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. a powerline communications device only provided connectivity to 70-80% of the outlets reliably. To help the power line communication signal to cross over different phases of an electrical system. Therefore. The amount of signal energy that transfers across power lines that are connected to different phases of a home’s power grid is called cross phase coupling. and the number of undetermined outlets. as it defines a relative throughput performance index within an average home for some percentage of total outlets. most of these impairments no longer are an impediment to performance. as an example. The percentage of outlets or electrical devices within a home that can receive and process power line data signals is referred to as a statistically derived “home coverage” figure. the size of the wire. This is different than an average performance figure. While some of these cross phase couplers could be installed by the homeowner at outlets that had both phases (e. Looking at the early implementations of powerline communications systems. A number of factors influence overall performance. Older (legacy) power line communication systems had challenges with wiring systems that used two or more phases of electrical power. 25 Mbps at 80% coverage should be interpreted as 80% of the power outlets in a house will provide at least 25 Mbps in bandwidth. including the distance the signals have to travel (size of home). connectivity to any outlet in a home is a virtual certainty. Whereas in the past.IPTV Basics
Device in the home) through a variety of conductive powerline pathways until it reaches a destination device. with the benefit of modern signal processing techniques and algorithms.g. The home coverage figure is important to a service provider. cross phase couplers could be installed. They were especially sensitive to noise impairments like brush motors.

This transformer produces two or three phases of power ranging from 110 V to 240 V.000 to 16. This diagram shows an X-10 power line communication system where an X-10 switch in the wall controls an X-10 outlet
Figure 7.6 shows how existing power line distribution systems in a home (such as X-10) can distribute data signals in a home. Figure 7.000 Volts) is supplied to a step down transformer near the home. but the improvements were not always enough to solve the overall challenges of connectivity and as a result. Power Line Communication Control System
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.6. This diagram shows that medium voltage electricity (6. operation of these home automation systems were not always reliable. These electrical signals pass through an electrical distribution panel (circuit breaker panel) in the home to supply outlets and lights.Chapter 7
couplers improved the home coverage ratio.

Set-Top Boxes. Digital Media Adapters (DMAs) and other media devices are already connected to power outlets already installed in a home or small businesses.
Coaxial
Coaxial cable premises distribution systems transfer user information over existing coaxial television lines in a home or building. Powerline distribution systems convert the different types of media (Internet data. Power line premises distribution for IPTV is important because televisions. This example also shows an X-10 power line control box plugged into another outlet on a different circuit (different phase) and the control signal must cross over from one phase to the other phase (cross over in the electrical panel) so it can reach the X-10 outlet receiver. or IP video streams) into information that is modulated onto high frequency carriers imposed on the powerline. Voice-over-IP packets. Although power line communication systems could technically transfer data in the 1970s and 1980s.IPTV Basics
receiver by sending control signals over the power line on the same circuit (same phase) to allow a user to control a lamp. improvements in the power line data transfer rates necessary for home data networking did not occur until the early 2000s.
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. These lines can be used to transmit rich multimedia content where it is desired. Intelligent powerline distribution systems are able to adapt to the varying characteristics of the in-home power grid and should be able to transfer media between any device enabled to “hear” the content being distributed on the powerline. Coaxial cable data transmission rates vary from 1 Mbps to over 1 Gbps and many homes have existing cable television networks and the outlets which are located near video accessory and television viewing points. Part of the motivation to make advances in power line communication was the increased need for home networking.

The tree may divide several times as it progresses from the root to each television outlet through the use of signal splitters. middle frequency bands for analog television channels.Chapter 7
Coaxial systems are commonly setup as a tree distribution system. As the length of coaxial lines increases and the number of ports (splitters) increases. a blocking filter may be installed. Coax lines to and from the cable television (CATV) company may contain analog and digital television and cable modem signals. In addition to the signal energy that is lost through the splitters. Figure 7. some signal energy is lost through attenuation on the coax cable itself. and upper frequency bands for digital television channels.
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. These frequency bands typically range up to 850 MHz. Coax premises distribution systems can use frequencies above the 850 MHz frequency band to transfer signals to cable television jacks throughout the house. The type of coaxial cable. Cable television distribution systems use lower frequencies for uplink data signals and upper frequencies for downlink data and digital television signals.7 shows how an in-home coaxial cable distribution system is typically used to distribute television signals in a home. To ensure the coax premises distribution signals do not transfer out of the home to other nearby homes. the signal frequency and the length of the cable determine the amount of energy that is lost. This example shows that the coaxial systems may use lower frequency bands for return connections (data modems). Some of the center frequencies are used for analog television signals. This cable connects to a signal splitter (and optionally an amplifier) that divides the signal and sends it to several locations throughout the home. Adapter boxes or integrated communication circuits convert the video and/or data signals to high frequency channels that are distributed to different devices located throughout the house. The root of the tree is usually at the entrance point to the home or building. the amount of attenuation also increases. This diagram shows that a cable connection is made at a demarcation (“demarc”) point on the outside of a home or building.

Coax is already installed in many homes.IPTV Basics
Figure 7. or IP video streams) into different portions of the frequency spectrum on the coaxial lines. Coax Television Distribution system
Smart coaxial premises distribution for IPTV is important because television and other media devices are already connected to a coaxial line that is already installed in a home or business. Because the coax cable is shielded and RF channels are virtually free from the effects of interfering signals. coaxial cable provides a large information pipe that is capable of distributing multiple wide radio frequency channels.7. Smart coaxial systems modulate different media (Internet data. These lines can be used to get multimedia information where you need it. and television outlets are com-
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. voice-over-IP packets. Smart coaxial distribution systems are usually able to distribute or interconnect media between several devices simultaneously.

and downlink data signals. VCRs and cable modems. Telephone line outlets may be located near television viewing points making it easy to connect IP television viewing devices. If these RF amplifiers are used. Coaxial cable is easy to install and expand.Chapter 7
monly located near media equipment such as televisions. Phone line premises distribution systems may use frequencies above the 1 MHz frequency band to transfer signals to telephone jacks throughout the house. These early telephone line data communication systems sent a limited amount of data using frequencies slightly above the audio frequency band.
Phoneline
Telephone wiring premises distribution systems transfer user information over existing telephone lines in a home or building. To ensure the phone line signals do not transfer out of the home to other nearby homes. they can introduce distortion and may block signals from two-way operation. If amplifiers are needed to strengthen the RF signal. To overcome some of the loss in a cable distribution system. These frequency bands typically range up to 1 MHz (some DSL systems go up to 12 MHz). The earliest telephone line home multimedia communication systems were used to allow computers to transfer files with each other (home data network) and to connect data communication accessories such as printers. uplink data signals. Telephone data transmission rates vary from 1 Mbps to over 300 Mbps. Adapter boxes or integrated communication circuits convert the video and/or data signals to high frequency channels that are distributed to different devices located throughout the house. they should be installed before the TVnet master device so as to prevent disruption of the IP network. a blocking filter may be installed. These early systems had relatively low data transmission rates and they
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. Telephone lines to and from the telephone company may contain analog voice signals. RF amplifiers are used.

Generally. looped or spliced throughout a house) and may have a variety of telephone devices and accessories attached to it. modems) and signals from outside source (such as AM radio stations). As the signals travel down the telephone lines. phoneline system use adaptive transmission systems.g. Phoneline data transmission involves converting data or information signals into a form (such as a modulated carrier frequency) that can travel along a communication line. the maximum signal level authorized by regulatory authorities (such as the Federal Communication Commission) is relatively low. a portion of the signal is lost through the wires (absorbed or radiated). DTMF. Figure 7. the amount of attenuation also increases. This diagram shows that an incoming telephone line is directly connected to all telephone outlets in the home or building. the lines are simply connected in sequence. as the length of a telephone increases and the number of outlets increases. Signal frequency. the lines are spliced together and in other cases.8 shows how existing phoneline distribution systems in a home or business can be used to distribute both voice and data signals in a home or building.IPTV Basics
were fairly limited when compared to automatic telephone line communication systems. A challenge for transmitting data over the phoneline is the presence of interfering signals and the variability of the characteristics of the telephone lines. To overcome the effects of interference and the variability of transmission lines. This example shows that a phoneline data network uses frequencies above the telephone line audio to distribute the data signals by sharing the phoneline. Variability can be caused by poor installation of telephone wiring. Phoneline data communication systems need to work through existing telephone lines (which may be unshielded) that are connected with each other in a variety of ways (e. telephone cords and changes in the characteristics of the telephone devices and accessories. In some cases. how the wire is installed and the length of the wire are key factors in determining the amount of energy that is lost. Because some of the energy leaks out of the telephone line. the type of wire. Interference signals include telephone signals (ringing.
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.

MoCA and 802. Development of the HomePlug specification is overseen by the HomePlug® Powerline Alliance.11 WLAN. twisted pair. protocols and transmission lines that are used to distribute communication services in a home or building. Phoneline Communication System
Premises Distribution Systems
Premises distribution systems are the combination of equipment. HomePNA™. Premises distribution systems may be used on one or several types of transmission lines such as coax.8. Some of the more popular types of premises distribution systems used for IPTV systems include HomePlug™. powerline or wireless.
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.
HomePlug™
HomePlug is a system specification that defines the signals and operation for data and entertainment services that can be provided through electric power lines that are installed in homes and businesses. TVNet.Chapter 7
Figure 7.

variability in the amount of coupling across different phases of electrical circuits and stray transmission. Interference signals include motor noise. Generally. The HomePlug 1.0
HomePlug 1. motors are in a variety of appliances and they may be used at different loca-
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. radio interference.0 is a powerline data communication system that transfers data through existing power lines at 14 Mbps using higher frequencies (from 4 MHz to 21 MHz).IPTV Basics
HomePlug 1. Because it is possible for HomePlug signals to travel on power lines shared between several homes. The HomePlug system was designed to overcome these types of interference and in some cases. Signal frequency. Signal loss at high frequencies through power lines can reach 50 dB and the dynamic range of HomePlug devices can be between 70 dB to 80 dB. a portion of the signal is lost through the wires (absorbed or radiated). the signals are encrypted to keep the information private. As the signals travel down the power lines. As a result. In most homes. the type of wire. Motor noise is the unwanted emissions of electrical signals produced by the rapidly changing characteristics of a motor assembly. Only devices that share the same HomePlug encryption codes can share the information transferred between the devices. One of the significant challenges for power line communication systems is the “sources and effects” of interference signals that can distort power line communication signals. changes in electrical circuit characteristics. the coverage of HomePlug power line communication systems approached 99% without the need for cross phase couplers or professional installers. the HomePlug system can take advantage of them.0 system encrypts (scrambles) information using 56-bit DES security coding. signal reflections. as the length of a power line increases and the number of outlets increases. the amount of attenuation also increases. The HomePlug system uses a higher frequency range than previous powerline data communication systems which enables signals to couple phases in the electrical distribution panel. how the wire is installed and the length of the wire are key factors in determining the amount of energy that is lost.

a reflected signal is generated. the sub-channels that are affected can be shut off. Each device that is a part of an in-home HomePlug network requires a HomePlug adapter or a HomePlug converter built into the device. When high-frequency HomePlug signals reach the ends of power lines. The HomePlug system can adapt in real time to the distortions caused by motors and appliances. The HomePlug system divides the frequency band into many independently controlled sub-channels (using a modulation scheme known as Orthogonal Frequency Division Multiplexing – OFDM) so that when interference is detected (such as from a hair dryer). The HomePlug system is smart enough to sense and adjust for the signal channels due to changes in electrical circuit characteristics.Chapter 7
tions at any time. The HomePlug system includes sophisticated analysis of the signal and it is possible to use the signal reflections as an advantage rather than a challenge. Another common challenge with home power line communication is the dynamic change that can occur in electrical circuit characteristics as users use light switches and plug into or remove electrical devices from outlets. The adapters also coordinate access to the power line communication system by first listening to ensure there is no existing activity before transmitting and stopping transmission when they detect information packet collisions have occurred. Because there are so many available sub-channels. Some of the energy of the forward signal (incident signal) is redirected (reflected) back towards the signal source. The HomePlug adapters convert information signals (digital data) into frequency carriers that travel down the power line. this has little effect on the overall capacity of the HomePlug system.
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. some of their signal energy is reflected back towards the transmitter. Signal reflection is the changing of direction that a signal travels as it passes from one transmission medium to another (transmission channel or device). Some of the frequencies used by HomePlug systems are the same radio frequencies used by citizen band (CB) radios or AM broadcast radio stations. When the characteristics of the media are different (impedance). These reflected signals combine with the forward (incident) signals producing distortion.

HomePlug 1.IPTV Basics
Figure 7.0 Distribution System
250
. This example shows that a computer can send a data signal to a printer located at an outlet in another room. it jumps across the circuit breakers and travels down the electrical lines to reach the HomePlug 1.0 system allows a power line distribution system to transfer data between devices connected to electrical outlets in a home.9.
Figure 7. This example shows several computers operating in a home and communicating between other data communication devices plugged into outlets.0 adapter connected to a printer. This diagram shows that the high frequency signals from the computer travel down the electrical line to the electrical panel. Then at the electrical panel to the power line communication signal. This diagram also shows that the computer can send data signals down the power line to a HomePlug router connected to a broadband modem allowing the computer to connect to the Internet.9 shows how the HomePlug 1.

to provide home media networking. The HomePlug AV system uses nearly 1000 separate narrowband carriers. as MAC efficiency needs to be contemplated in overall performance measurements. The HomePlug AV system uses a more secure 128-bit AES encryption process to keep information private. Because it operates at high frequencies. HomePlug AV was designed to give priority to media that requires time sensitive delivery (such as IPTV) while allowing reliable data communication (such as web browsing) to simultaneously occur.0. HomePlug AV uses a significantly higher spectrum (from 2 MHz to 28 MHz) which allows for good cross phase coupling because these higher frequencies can jump across circuit breakers to increase the signal availability in the home. it does not interfere with power line control systems such as X-10. The system can selectively shut off these narrowband carriers (frequency notches) when it senses interference. each platform that will be part of the HomePlug AV network requires a HomePlug AV adapter or a HomePlug AV transceiver built into the device. Like HomePlug 1. Actual application layer performance will be less than that.Chapter 7
HomePlug Audio Visual (HomePlug AV)
The HomePlug Audio Visual (HomePlug AV) specification was ratified in 2005 by the HomePlug Board of Directors. The adapters coordinate access to the
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. the coverage of HomePlug AV power line communication systems approaches 99% without the need for cross phase couplers or professional installers. Like the HomePlug 1.0 system.0 system. The HomePlug AV system is designed to be a 200 Mbps-class PHY device. HomePlug AV uses a mix of random access (unscheduled) and reserved access (scheduled) data transfer. The carrier sense multiple access with collision avoidance (CSMA/CA) protocol. which provides for efficient transfer of bursty data while the scheduled TDMA system ensures real time media (such as digital video and audio) will be delivered without delays and will take priority on the wire over CSMA/CA traffic. The HomePlug AV system has better control of transmission delays (latency and jitter) and is designed to co-exist with the HomePlug 1.

Figure 7.10.IPTV Basics
power line communication system. an IPTV service provider is sending a movie through a broadband modem to a television in the home. This example shows that a HomePlug adapter coordinates the transmission of signals without interfering with the transmission between other devices. In this diagram. This coordination involves either reserving time periods for transmission and/or dynamically coordinating access by listening to the signals on the power line to ensure there is no existing activity before they transmit and stopping transmission when they detect data transmission collisions have occurred.10 shows how a HomePlug AV system can allow a power line distribution system to dynamically interconnect devices by connecting devices to electrical outlets and using high frequency signals to transfer information. This example shows that the HomePlug system uses a HomePlug AV router to receive the signals from the broadband modem and route the information through the power lines to the television in the home using dedicated time slots to
Figure 7. HomePlug AV Distribution System
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.

which allows a connection to an adapter or have a HomePlug AV transceiver embedded within a platform. Each device connected to a HomePlug system must have an Ethernet or USB port. a computer is connected through a HomePlug AV adapter to the inhome broadband modem allowing it to connect to the Internet and transfer data on an “as available” basis. HomePlug bridges allow data packets to cross over into devices or other networks without any need to use configuration utilities. Adapters can be simple conversion devices (Ethernet to HomePlug) or they can include some packet transfer capability (routers or bridges). It is possible for customers to self-install a HomePlug AV system. HomePlug devices include nodes and bridges.0 with Turbo. Nodes simply convert data signals into the frequency signals that travel on the power lines. the HomePlug AV system can have data transmission rates in excess of 100 Mbps. Even with the overhead control information. While most HomePlug devices are pre-configured with the most common settings. it is possible to customize the configuration of the HomePlug adapter devices by connecting them to a local computer and allowing the user to change key settings such as IP addresses and passwords.
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. There is a difference between physical data transmission rates (the “PHY” rate) and actual data throughput. CeBus and LONworks. X-10. This example shows that simultaneously. A HomePlug Ethernet bridge allows packets from a HomePlug network to enter into an Ethernet network (such as allowing data to the Internet). HomePlug 1. HomePlug AV technology is designed to co-exist with a variety of other systems including HomePlug 1. The system is setup to automatically detect (discover) other devices in the network. The adapter can be an external box or it can be designed into a product (such as a CD player). The HomePlug AV powerline technology theoretical PHY transmission rate is 200 Mbps.0.Chapter 7
ensure a reliable quality of service (QoS). The throughput is affected by the amount of overhead (control) data and the amount of information that is lost via interference and the access control process.

each device must have an adapter or bridge to convert the information or data into a HomePNA signal. routers. gateways. Digital subscriber line (DSL) systems typically occupy frequency bands from the audio range up to approximately 2 MHz. looped or spliced throughout a house) and may have a variety of telephone devices and accessories attached to it. A broadbased product ecosystem is rapidly forming for HomePlug AV technology. To connect to the HomePNA network. HomePlug technology generally works in most homes. DMAs and entertainment electronics platforms. Phoneline data communication systems need to work through existing telephone lines (which may be unshielded) that are connected with each other in a variety of ways (e. TVs.g. The HomePNA system has been designed to co-exist with both telephone signals (lower frequency range) and digital subscriber line signals.IPTV Basics
The typical range of a HomePlug signal is approximately 1000 feet (300 meters). This ecosystem includes set-top boxes. Phoneline data communication systems use adapters to convert information from digital format to signals that can travel along the telephone lines. Sending broadband information over the same wires used to transfer telephone lines and coaxial lines involves converting the information into signals that can be transferred down these existing wires without interfering with other existing signals. switches. products and services.
HomePNA™
The HomePNA is a non-profit association that works to help develop and promote unified information about a home multimedia network technologies. HomePNA initially started by defining home data networks over telephone lines and it has expanded its focus to multimedia distribution over telephone and coaxial lines. HomePlug devices that are certified to operate under the HomePlug specification will interoperate with each other. Adapters
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. video and data over telephone lines or coaxial lines. displays. The HomePNA system has now evolved into a high-speed home multimedia communication network that can transfer digital audio.

The changes can include changing the modulation type and/or data transmission rates to ensure communication between devices connected to the HomePNA system is reliable.0 was the first industry specification that allowed for the use of data transmission over telephone lines. DTMF. A gateway or bridge may be used to link the HomePNA network to other systems or networks (such as the Internet). telephone cords and changes in the characteristics of the telephone devices and accessories. modems) and signals from outside source (such as AM radio stations). the HomePNA system uses an adaptive transmission system.0 system has a data transmission rate of 1 Mbps with a net throughput of approximately 650 kbps. To overcome the effects of interference and the variability of transmission lines.3).0 is a home networking system that is designed to provide medium speed data transmission rates and to allow priority to the transmission of different types of media.0 systems are very low cost and are used throughout the world. The HomePNA 2.Chapter 7
or bridges can be separate devices or they can be integrated into a device such as set top box. The adapters convert standard connection types such as wired Ethernet (802. They are popular in multi-tenant units in the far east.0
HomePNA 1. The HomePNA system was designed to allow a gateway (such as a residential gateway .
HomePNA 2.0
HomePNA 2. A challenge for transmitting data over the phonelines is the presence of interfering signals and the variability of the characteristics of the telephone lines. universal serial bus (USB).
HomePNA 1. Interference signals include telephone signals (ringing. The HomePNA system monitors its performance and it can change the transmission characteristics on a packet by packet basis as the performance changes.0 system has a data
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. Firewire (IEEE1394) and others. The HomePNA 1. HomePNA 1. Variability can be caused by poor installation of telephone wiring.RG) to be located anywhere in the home.

The data transmission rate is constantly adjusted on a
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. The HomePNA 3.0 system has a data transmission rate of 240 Mbps with a net data transmission throughput of approximately 200 Mbps and it is backward compatible with HomePNA 2.0 uses either quadrature amplitude modulation (QAM) for high-speed transmission or frequency diverse quadrature amplitude modulation (FDQAM).9954. The HomePNA 2.0 system including prioritized transmission for different types of media and an optional form of modulation to help ensure more reliable transmission during interference conditions.0 system included the ability to transmit data using a modulation scheme known as Frequency Diversity Quadrature Amplitude Modulation (FDQAM). The FDQAM performs spectral multiplication where the same signal is transmitted on different frequencies (frequency diversity). the modulation type can change from QAM to FDQAM increasing the robustness (reliability) of the signal. When interference is detected (such as from an AM radio station). Depending on the quality of the transmission line and the media requirements.0
HomePNA 3. HomePNA 3. These prioritized services included IP telephone and video services where longer packet transmission delays were not acceptable. The HomePNA 2.
HomePNA 3.0 is a multimedia home networking system that is designed to provide high-speed data transmission rates and to control the quality of service for different types of media. The industry standard has been adopted by the ITU as specification number G.0 system added new capabilities to home networking from the previous HomePNA 1. Transmission prioritization of was added to the HomePNA system to allow for differentiation and prioritization of packets for time sensitive services.IPTV Basics
transmission rate of 16 Mbps with a net data transmission throughput of approximately 8 Mbps. HomePNA 3.0 was standardized in June 2003 and commercial products were available starting in May 2004.0.

The HomePNA 3. Each HomePNA 3.0 system.0 system added the ability to the mix of controlled (contention free) and on demand (random access) transmission to home networking. This example shows that scheduled devices only transmit during their assigned schedules and other devices compete for access during the remainder (unscheduled portion) of the media cycle.0 system accomplishes this by assigning one of the HomePNA devices in the system as a master control unit. an IPTV service provider can setup the residential gateway (broadband modem) to be the master unit of the HomePNA system. The HomePNA 3. The master can be selected automatically or it can be manually setup or programmed as the master. If the master unit is shut off or if it becomes disabled. Figure 7. The master coordinates all of the bandwidth reservation and transmission assignment and all the other units are slaves that follow the lead of the master.11 shows a HomePNA 3. the HomePNA system will automatically setup another unit as the master.Chapter 7
packet by packet basis by varying the symbol rates (increasing and decreasing the amount of shifts per second) and the number (precision) of decision points per symbol to ensure data can be received in varying conditions. This diagram shows that the master unit periodically sends MAP message and that each MAP message identifies which devices are assigned synchronized transmission and when unscheduled transmissions may occur. A media access plan is a list of devices and their assigned transmission schedules and priorities for media transmission.
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. The Master unit coordinates the transmission time periods of all of the HomePNA devices in the system through the periodic transmission of a media access plan message.0 system can provider for a mix of synchronized (guaranteed) and random access (unscheduled) transmission through the use of a master controller. The HomePNA 3. For example.0 device is typically capable of acting as a master or a slave.

the HomePNA 3.IPTV Basics
Figure 7.11.1 system uses the same frequency band for the telephone line and coaxial line.1 is a multimedia home networking system that is designed to provide high-speed data transmission rates and to control the quality of service for different types of media over both telephone lines and coaxial cables. The HomePNA 3.1 system is backward compatible with HomePNA 3. The HomePNA 3. When operating on the coaxial line.0 Distribution System
HomePNA 3. Because the coaxial line is a shielded line. the HomePNA system can increase its
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.1
HomePNA 3. HomePNA 3.1 system only uses the scheduled mode which can be more than 90% efficient increasing the data rate available for the users.1 system has a data transmission rate of 320 Mbps with a net data transmission throughput of approximately 250 Mbps.0 and HomePNA 2. This frequency band is above digital subscriber line signals and is below television channels.0 The HomePNA 3.

1 system can use both telephone line and coaxial lines to be used.000 feet (1.
Figure 7.500 meters). HomePNA 3.
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. data and video signals over both telephone lines and coaxial lines allowing it to be available at more locations in the home. allowing the effective distance the HomePNA system can operate to over 5. Figure 7.0 Phoneline and Coax Distribution
Figure 7. This diagram shows that the HomePNA system can be used to distribute voice.12 shows how a HomePNA 3.13 shows a summary of the different types of HomePNA systems and their capabilities.Chapter 7
power (called “power boost”). This table shows that the HomePNA system has evolved from a low speed data only to a high-speed multimedia multiple line type home networking system.12. The HomePNA system allows devices to directly communicate with each other.

g.
Digital Home Standard (DHS)
Digital home standard is a system specification that defines the signals and operation for data and entertainment services that can be provided through electric power lines that are installed in homes and businesses.
Figure 7.org. HomePNA devices that are certified to operate under the HomePNA specification will interoperate with each other. While this interference would typically only reduce the performance (e. data transmission rate). HomePNA Capabilities
Some telephone devices and accessories that are lower quality can create interference with the HomePNA system.13. More information about DHS can be found at www. Development of the DHS specification is overseen by the Universal powerline association (UPA). installing microfilters to block the unwanted interference from the telephone devices can solve it.IPTV Basics
The typical range of a HomePNA signal is approximately 1000 feet (300 meters) on telephone lines.
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ensuring that devices do not try to communicate over the top of one another. The TVnet system uses RF modulation technology to allow IP packets (whether video. the master serves as the arbiter on the coax. which allows for the establishment and control of communication sessions. This prevents a problem on the network. This ensures that TVnet signals will not interfere with channels received from another television service provider. The TVnet system uses an Ethernet type access structure that allows IP packets to be transferred between devices. Essentially. deciding which target TVnet device is permitted to communicate at which time. Because multiple devices may be networked on a TVnet system. voice. thus enabling target devices to send and receive IP traffic. The HD-PLC system transmits high-speed data signals using frequencies between 4 MHz to 28 MHz. For example. It has a maximum transmission distance of approximately 150 meters. The TVnet multimedia distribution system operates by transferring media on unused frequency bands on the coaxial cable system.Chapter 7
HD-PLC
High definition power line communication is communication system developed by Panasonic that uses high frequency signals over a power line to transmit data and digital media signals. or data) to be
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. the TVnet/C network uses the coax spectrum above 1 GHz. TVnet enables users to distribute many kinds of media throughout the home on a coaxial distribution system. The HD-PLC system supports the use of 128 bit encryption to ensure data privacy. The TVnet master sends control commands between target devices.
TVnet
TVnet is a smart coaxial based media distribution developed by Coaxsys. the master control device in the TVnet system directs the flow of traffic on the network.

If the customer desires. or IP telephone. Figure 7. TVNet Distribution System
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. and convert the signal back to digital once it reaches its destination.IPTV Basics
transmitted over coax.14 shows how TVnet systems can allow a coaxial distribution system to dynamically interconnect devices by connecting devices to coax and using unutilized coax spectrum for the purposes of IP networking.14. such as an IP set-top box. Each device that will be part of the TVnet network requires a TVnet “target” adapter. At the same time. transmit the new analog signal over coax. TVnet devices convert the digital signal into an analog signal. they can also use the device’s pass-through port to allow cable television signals to pass directly through the TVnet target adapter. This example shows that a master coordinates the transmission of signals without interfering with the transmission between other devices. an IPTV head end streams a movie through a broadband modem to a television in another room. PC. This target will be located next to the Ethernet device. In this diagram. a computer is connected
Figure 7.

This example also shows that the master device in this coax system has the capability to setup connections and prioritize transmissions based on the type of media (such as real time video over web browsing data). and over 200 Mbps has been demonstrated. Alternatively. providing a total of 9 devices with the basic system. However.Chapter 7
through a coax cable to the broadband modem to the Internet and a television is connected to a media server through the broadband modem. The TVnet/C is setup to allow eight target connections for each master unit. operators deploying in single-family homes typically deliver IPTV to 2-4 televisions. a TVnet Master and TVnet Targets. The TVnet system typically achieves actual throughput rates of 70 to 100 Mbps.
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. An important consideration about data transmission rates is the difference between physical data transmission rates (the “PHY” rate) and actual data throughput. The user can also connect to multiple digital devices at any one connection point. there are some applications such as IP video on demand or IPTV installations in multiple dwelling units (MDUs) that use far more Targets per Master than the typical 2-4. No other software. so the number of devices that can be connected is far higher than nine. There are two key types of equipment that are needed for a TVnet system. The throughput is affected by the amount of overhead (control) data and the amount of information that is lost via interference and the access control process. However. they are relatively immune from interfering signals and can have higher throughputs that other types of premises distribution networks. In practice. TVnet technology can be integrated into the modem or set-top box. switch settings or configuration setups are required. the TVnet system can be expanded to virtually an unlimited number of connections. Because coaxial cable systems can transfer signals with minimal signal leakage.

The MoCA system uses 50 MHz transmission channel that transmit at 270 MHz.5 GHz using on the coaxial cable system [2].
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. the insertion loss (attenuation) is high. products and services that are primarily distributed over coax cabling systems within a building or premises. Home coaxial networks commonly are setup as a tree structure and there may be several signal splitters used in the tree. The MoCA system operates by transferring media on frequency bands between 860 MHz and 1. MoCA has developed a system for transferring multimedia signals over coax networks. signals from one device in the MoCA system must travel across splitters (“splitter jumping”). it can use up to 16 different channels that can be dynamically assigned and controlled. Each 50 MHz channel is subdivided into smaller channels using orthogonal frequency division multiplexing (OFDM) and the net throughput of each MoCA channel is 135 Mbps. The MoCA system is designed to prioritize the transmission of media to ensure a reliable quality of service (QoS) for various types of media. Because splitter jumping the transmits of a signal from a device connected to an output port to another device that is connected to a different output port of the coupler. The MoCA system can schedule (reserve) bandwidth so it can provide different QoS levels. The MoCA system was designed to operate with most existing home coaxial networks without requiring changes.IPTV Basics
Multimedia over Coax Alliance (MoCA)™
Multimedia over Coax Alliance is a non-profit association that works to help develop and promote unified information about networking technologies. Because the MoCA system can have multiple devices and it may co-exist with other systems. The MOCA system uses DES for link level encryption to ensure privacy between neighboring devices and systems. These channels can operate independently allowing MoCA systems to co-exist together. To operate without any changes.

Link budget is the maximum amount of signal losses that may occur between a transmitter and receiver to achieve an adequate signal quality level. Coaxial amplifiers are devices or assemblies that are used to amplify signals that are transmitted on coaxial cables.15 shows how a MoCA systemizes a coaxial distribution system to dynamically interconnect devices by connecting devices to coax and using frequencies above 860 MHz. Drop amplifiers are signal amplifiers that have been inserted after a communication drop to a building and before other devices that are connected to the premises network. Coaxial amplifiers may offer unidirectional or bidirectional amplification capabilities. The link budget includes splitter losses. There are two types of coaxial amplifiers. Figure 7. about 2% of homes have in line amplifiers and approximately ½ of these homes may have challenges using a PDN system [3]. The frequency range and coaxial amplifiers is typically chosen to match the signals that are transmitted on the coaxial cable. cable losses and signal fade margins. Inline amplifiers can be a potential block for coaxial distribution signals. Coaxial amplifiers may be used on home television systems that have long cable connections or that have many television ports (many splitters).
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The MoCA system enables splitter jumping by having a large link budget. This example shows that the MoCA system is designed to operate in an existing cable television system by allowing signals to jump across and through existing splitters. Inline amplifiers are signal amplifiers that have been inserted into a premises network where it is located between (inline with) devices. In the United States. drop amplifiers and inline amplifiers. A potential challenge for bi-directional coaxial distribution systems is the use of coaxial amplifiers.

reliable distribution of IPTV signals over consumer-grade Wi-Fi systems have not been possible.IPTV Basics
Figure 7. Wi-Fi is fundamentally an unreliable medium due to that fact that it is shared among multiple users over the unlicensed RF spectrum. range and data transmission rates.11 Wireless LAN
802. The use of unlicensed frequency bands can result in interference from other devices that used the same frequency bands.11 Wireless LAN (commonly called “Wi-Fi”) is a set of IEEE standards that specify the protocols and parameters that are used for commonly available wireless LANs that use radio frequency for transmission. The use of Wi-Fi systems for IPTV distribution offers the advantage of requiring “no new wires. This includes interference that
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.” Wireless LAN systems operate in the unlicensed frequency bands. Until recently. MOCA Distribution System
802. signal quality levels.15. The key challenges that face providers and subscribers running IPTV over Wi-Fi is radio signal interference from other sources.

This example shows that there are several different communication sessions that are simultaneously operating in the same frequency band and that the transmission of these devices are not controlled by any single operator. These devices do cause some interference with each other and the types of interference can be continuous. For the microwave oven.16 shows typical types of unlicensed radio transmission systems that can cause interference with WLAN systems. For the wireless head-
Figure 7. short-term intermittent or even short bursts.16.Chapter 7
may come from other Wi-Fi systems that operating nearby or microwave ovens or other obstructions that may dynamically appear and cause problem in the transmission of video over Wi-Fi. Figure 7. For the cordless telephone. For the video camera (such as a wireless video baby monitor). the transmission occurs over several minutes at a time. the transmission is continuous. the radio signals (undesired) occur for very short bursts only when the microwave is operating. Wireless LAN Interference
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the transmission occurs for relatively long periods of time but the power is very low so interference only occurs when the wireless headset gets close to WLAN devices. cordless telephones. 802. In short. have drastically different protocols which are used by devices to gain access to the network. Medium access control (MAC) is the processes used by communication devices to gain access to a shared communications medium or channel. while still providing an interface that upper layer protocols.
802.11n MIMO and smart antenna systems in increase the reliability and performance of the Wi-Fi system. The 802. the MAC provides an abstract service layer that allows network layer protocols
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. Wi-Fi systems that are used for IPTV systems. for example Ethernet.11e Quality of Service
The 802. This results in sub-standard video that freezes or has an unacceptable amount of artifacts.IPTV Basics
set. they must be able to support quality of service for different types of media. and data communication.11 series of WLAN specifications that added quality of service (QoS) capabilities to WLAN systems. If it cannot. a user watching an IPTV stream might have their viewing interrupted when another user is downloading a file over the same Wi-Fi network.11e quality of service. Token Ring or FDDI. Sources of WLAN interference are varied and many including microwave ovens. Each networking technology. In addition to overcome potential interference issues. Wi-Fi systems that are used for IPTV multimedia home network may use a combination of 802. video. MAC is part of the OSI model Data-Link Layer.11e wireless local area network is an enhancement to the 802. such as TCP/IP may use without regard for the details of the MAC protocol that is used. baby monitors. Radio interference can cause lost packets. A MAC protocol is used to control access to a shared communications media (transmission medium) which attaches multiple devices. neighboring Wi-Fi networks and even people.11e specification modifies the medium access control (MAC) layer to allow the tracking and assignment of different channel coding methods and flow control capabilities to support different types of applications such as voice.

a hybrid coordination function controlled channel access (HCCA) can be used.11 system so it can assign and coordinates transmission and tasks that are assigned to other devices. The HCCA process can guarantee reserved bandwidth for packets classified by using the EDCA process.. The prioritization is enabled through the assignment of different amount of channel access back-off times where the amount of back-off time depends on the packet priority.11n Multiple Input Multiple Output (MIMO)
The 802. The 802.
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.11n wireless local area network is an enhancement to the 802. video.11 series of WLAN specifications that added quality of service (QoS) capabilities to WLAN systems.11e wireless local area network is an enhancement to the 802.11 series of WLAN specifications that adds multiple input and multiple output (MIMO) capability to WLAN systems.Chapter 7
to be indifferent to the underlying details of how network transmission and reception operate. and data communication. The central arbiter receives transmission requests from all the devices communicating in the 802.
802. Enhanced distributed channel access is a medium access control (MAC) system that is used in the 802.11e specification modifies the medium access control (MAC) layer to allow the tracking and assignment of different channel coding methods and flow control capabilities to support different types of applications such as voice.11e WLAN system that enables the assignment of priority levels to different types of devices or their applications. To coordinate and prioritize packets between devices within an 802. The 802. The HCCA uses a central arbiter (access coordinator) that assigns the access categories for different types of packets.11 network. The 802. EDCA defines four priority levels (four access categories) for different types of packets.11n specification modifies the medium access control (MAC) layer to allow channel bonding (channel combining) and this increases the available data transmission rate while increasing the reliability (robustness) of the Wi-Fi system.

17. Multiple Input Multiple Output (MIMO)
Smart Antenna System
A smart antenna system uses active transmission components to allow the forming or selection of specific antenna patterns. Smart antennas may have multibeam capability that allows for the reuse of the same frequency in the same radio coverage area.IPTV Basics
Multiple input multiple output is the combining or use of two or more radio or telecom transport channels for a communication channel. This example shows that even if an object or signal distortion occurs in one of the transmitted paths. Using smart antenna systems. the transmission energy of a signal can be directed in a specific direction that does not result in the interference to other signals that are operating in the same general area.17 shows how a multiple input multiple output (MIMO) transmission system transmits signals over multiple paths to a receiver where they are combined to produce a higher quality signal. Figure 7.
Figure 7. The ability to use and combine alternate transport links provides for higher data transmission rates (inverse multiplexing) and increased reliability (interference control). data can still be transmitted on alternative paths.
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This example shows that a wireless access point has been enhanced to allow the transmission of signals using directional antennas so that signals can be sent to specific devices. In this diagram.g. Wi-Fi Television) is not direct as a metal art object that is located between the AP and the WiFi device reflects the radio signal.
Figure 7. Smart Wireless LAN
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. forcing that receiver to provide an acknowledgement. one of the best paths between the access point (AP) and Wi-Fi device (e.Chapter 7
Wi-Fi systems that have smart antenna capability can alter multicast traffic by directing the traffic to a specific receiver. This example also shows that this WLAN system has the capability to prioritize transmission based on the type of media (such as real time video over web browsing data).18. This way the system knows if the video transmission was received and the quality of the link.18 shows how WLAN systems can be improved through the use of directional transmission and media prioritization to provide improved performance. Figure 7.

DSL modem. wireless or optical systems. The network interface for IPTV end user devices allow it to receive IP data. decoding. The device must separate out (demultiplex) the communication channel from the network connection (if necessary) and separate out the component parts of the television signal (video. The key functions for end user devices include interfacing to the communication network. The network interface may receive and transmit signals on broadband CATV. The underlying media is then decoded and decrypted (unscrambled). Figure 8. IP end user devices are commonly located in a customer’s home to allow the reception of video signals on a television. DSL. rendering and user interface selections. The signal processing section receives. These interfaces include Ethernet. selects and demultiplexes the incoming channels. the channel may require decoding (decryption) for scram-
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. selecting and decoding channels.1 shows the basic functions of an IPTV end user viewing device. satellite. The media is then converted (rendered) into a form that can be displayed or heard by the end user. signal processing. cable. audio and data). processing the media into a form usable by humans and providing controls that allow the user to interact with the device. This diagram shows that the end user device has a network interface.Chapter 8
IPTV End User Devices
IPTV end user devices adapt an IP communications medium to a format that is accessible by the end user. After the channels are received. A program guide and menu system is provided to allow the user to navigate and select features and services. optical or wireless connections.

The STB then converts the data into signals that can be displayed to the viewer (rendering). IP televisions. The STB has a user interface that allows the system to present information to the user (such as the program guide) and to allow the user to interact (select channels) with the STB.1.
Set Top Boxes (STB)
A set top box is an electronic device that adapts a communications medium to a format that is accessible by the end user. multimedia computers and portable media players.
Figure 8. Set top boxes are commonly located in a customer’s home to allow the reception of video signals on a television or computer. IPTV User Device Functions
The key types of end user devices used in IPTV systems include set top boxes (STBs).IPTV Basics
bled channels.
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. multimedia mobile telephones.

Download and Play (DP STB)
Download and play set top boxes are devices that can select. Because download and play STBs wait until programs are completely downloaded before playing.g. The use of HSTBs allows a viewer to get direct access to broadcast content from terrestrial or satellite systems in addition to accessing other types of systems such as interactive IPTV via a broadband network. they can transfer programs through unmanaged networks (such as the Internet) and play the programs without errors or delays. An IP STB is basically a dedicated mini computer. Hybrid set top boxes are commonly located in a customer’s home to allow the reception of video signals on a television or computer. IP STBs must convert digital broadband media channels into the television (audio and video signals) and decode and create the necessary control signals that pass between the IP STB and system headend equipment. Using IP STBs. HDMI). NTSC. PAL. which contains the necessary software and hardware to convert and control IP television signals.
Hybrid STB
A hybrid set top box is an electronic device that adapts multiple types of communications mediums to a format that is accessible by the end user.
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Internet Protocol Set Top Box (IP STB)
IP set top boxes are devices that convert IP packet signals into analog or digital television formats (e. completely transfer (download) and play media programs. it is possible to use standard televisions for viewing television channels that are sent over a data network such as DSL or over the Internet.

Multimedia Computers
A multimedia computer is a data processing device that is capable of using and processing multiple forms of media such as audio. Mobile telephones usually have limited information processing capability. IP televisions contain embedded software that allows them to initiate and receive television signals through that network using multimedia session protocols such as SIP. picture tube or plasma display). media players in mobile telephones may use compression and protocols that are more efficient than what are used by standard IP television systems. data and video. Because of the limited bandwidth and higher cost of bandwidth for mobile telephones.
Mobile Video Telephones
Mobile video telephones have multimedia capabilities that allow them to receive and display video signals. Multimedia mobile telephones contain embedded software that allows them to initiate and receive multimedia communication sessions through the Internet. mobile telephone data sessions may be connected through gateways that compress media signals and convert standard control protocols to more efficient and robust control protocols. To increase the efficiency. small displays and may have restricted access to Internet services.
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. IP televisions also include the necessary software and hardware to convert and control IP television signals into a format that can be displayed on the IP television (e. An IP television has a data connection instead of a television tuner.IPTV Basics
IP Television (IP Television)
IP televisions are television display devices that are specifically designed to receive and decode television channels through IP networks without the need for adapter boxes or media gateways.g. This may cause some incompatibilities or unexpected operation for mobile television systems.

decoding (if the signal is encrypted) and displaying of the program to the monitor. storage. maintain a connection. audio and graphics).
IP STB Capabilities
IP STB capabilities include network connection types. a soft client is used.
Portable Media Players
A portable media player is a self-contained device and associated software application that can convert media such as video. To securely present IPTV signals on a multimedia computer (to ensure the television program is not stored. The soft client coordinates the transmission. display capability.Chapter 8
Because many computers are already multimedia and Internet ready. accessories. media processing (video. and manages the call connection. mouse. Control of IP television on a multimedia computer can be performed by the keyboard. reduced navigation controls and limited signal processing and decoding capabilities. audio or images into a form that can be experienced by humans. communication protocols. and process television control features. Portable media players may have small display areas with limited resolution capability. media distribution and upgradeability. The media player must be able to find and connect to IP television media servers. software applications. The media player software controls the sound card. or external telephone accessory device (such as a remote control) that can be connected to the computer through an adapter (such as an infrared receiver). accessories (such as a handset). A soft client is a software program that operates on a computing device (such as a personal computer) that can request and receive services from a network for specific applications. process compressed media signals.
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. it is often possible to use a multimedia computer to watch IP television through the addition or use of media player software. copied and distributed). middleware compatibility. security.

Display capabilities for IP STB include size and resolution (SD or HD).
Dual Display (Picture in Picture)
Picture in picture is a television feature that allows for the display of one or more video images within the display area of another video display. Picture
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. DSL. Common network connection types for IPTV viewing devices include Ethernet. it is called picture in graphics. Picture in graphics may be used to display other media items (such as a channel menu).IPTV Basics
Network Connection Types
Network connection types are the physical and system connections that may be used to provide communication services. Display capabilities for television systems are characterized in the MPEG industry standards and the sets of capabilities (size and resolution) are defined as MPEG profiles. Satellite and DTT.
Video Scaling
Video scaling is the process of adjusting a given set of video image attributes (such as pixel location) so they can be used in another format (such as a smaller display area).
Display Capability
Display capability is the ability of a device to render images into a display area. Cable. Video scaling can be used to reduce the size of a display to an area that allows for placing it or surrounding it within a video picture or within in a graphics image. When a video program is placed within a graphic image. the type of video (interlaced or progressive) and display positioning (scaling and displaying multiple sources). Set top boxes often have multiple network connection types and there may be multiple service providers who can provide services through the STB.

Smart card software can be embedded (included) in the set top box to form a virtual smart card. A virtual smart card is a software program and associated secret information on a users device (such as a TV set top box) that can store and process information from another device (a host) to provide access control and decrypt/encrypt information that is sent to and/or from the device.
Smart Card
A smart card is a portable credit card size device that can store and process information that is unique to the owner or manager of the smart card.
Security
Security for set top boxes is the ability to maintain its normal operation without damage and to ensure content that is accessed by the STB is not copied or used in an unauthorized way by the user. Smart cards are used with devices such as mobile phones. To obtain two picture sources. Smart cards can be used to identify and validate the user or a service. electrical pads on the card connect it to transfer information between the electronic device and the card. Set top boxes commonly include smart cards and security software to ensure the content is used in its authorized form.
DRM Client
A digital rights management client is a computer.
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. When the card is inserted into a smart card socket. They can also be used as storage devices to hold media such as messages and pictures.Chapter 8
in picture typically allows a viewer to watch two (or more) programs simultaneously. it usually requires that the STB has multiple receivers. television set top boxes or bank card machines. hardware device or software program that is configured to request DRM services from a network.

IPTV Basics
An example of a DRM client is a software program (module) that is installed (loaded) into a converter box (e. Audio processing is the methods that are used to convert and/or modify audio signals from one format into another form using signal processing. PAL or NTSC video). data or video). audio processing and graphics processing.
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Secure Microprocessor
A secure microprocessor is a processing device (such as an integrated circuit) that contains the processes that are necessary to encrypt and decrypt media. Video processing is the methods that are used to convert and/or modify video signals from one format into another form using signal processing.g. Media processing in set top boxes includes video processing. The processing of media ranges from the playback of voice messages to modifying video images to wrap around graphic objects (video warping). An example of audio processing is the decoding of compressed audio (MP3 or AAC) and conversion into multiple channels of surround sound audio (5. set top box) that can request and validate information between the system and the device in which the software is installed.
Media Processing
Media processing is the operations used to transfer.g. store or manipulate media (voice. An example of video processing the decoding of MPEG video and the conversion the video into a format that can be displayed on a television monitor (e. Secure microprocessors contain the cryptographic algorithms such as DES.1 audio). AES or PKI. The secure microprocessor can be a separate device or it can be a processing module that is located within another computing device (such as a DSP).

Trivial file transfer protocol (TFTP) is used to transfer programs and configuration files between the system and the STB. stop and move through media programs. Transport stream (TS) protocol coordinates how multiple media channels (video. IGMP. audio and data) share the same transmission channel.
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Graphics processing is the methods that are used to convert and/or modify image objects from one format into another form. PPPoE. Simple network management protocol (SNMP) is used to capture and change equipment settings. Point-to-point protocol over Ethernet (PPPoE) is used to setup and coordinate a communication link over an Ethernet connection. An example of graphics processing the conversion of text (e. Microsoft media server protocol (MMS) coordinates the transfer of multimedia objects and files. timing. sequence. MMS.g. DHCP. SNMP. and error checking used on a network or computing system. subtitles) into bitmapped images that can be presented onto a television display (on screen display). TFTP and HTTP. Internet group management protocol (IGMP) allows multiple users to share the same stream of media (e. Transmission control protocol and Internet protocol (TCP/IP) coordinates the transmission and reception of packets through IP networks. Some of the common protocols used in IP STB include. watch a TV program from a nearby router instead of setting a direct connection for each user). play. Communications protocols vary in complexity ranging from simple file transfer protocols to reservation protocols that setup and manage the reliability of connections through a network. Real time streaming protocol (RTSP) provides for media flow control to allow users to select. Dynamic host configuration protocol (DHCP) obtains the IP address that is used during communication between the STB and the system. Communication protocols define the format. Hypertext transfer protocol (HTTP) is used to select and coordinate transfer media and data files. RTSP.g. TS. TCP/IP. There are many types of protocols (with multiple versions and options) used by IP set top boxes.
Communication Protocols
Communication protocols are sets of rules and processes that manage how transmissions are initiated and maintained between communication points.

Accessories
IPTV accessories are devices or software programs that are used with IPTV systems or services. gaming controllers and other human interface devices that are specifically designed to be used with IPTV systems and services. Software applications in set top boxes may be in the form of embedded applications. These accessories may have dedicated connection points (such as game controllers) or they may share a standard connection (such as a USB connection).g. Examples of IPTV accessories include remote controls.
Middleware Compatibility
Middleware compatibility is the ability of a device to accept software programs (clients) that interface the device to the system host (servers).
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. A loader application (the loader is an embedded application) is used to request and transfer applications from the system. Downloaded applications are software programs that are requested and transferred from the system to the user device when needed. Embedded applications are programs that are stored (encapsulated) within a device. to request television programs from media network).IPTV Basics
Software Applications
A software application is a software program that performs specific operations to enable a user to apply the software to their specific needs or problems. Virtual applications are software instructions that are written in another language to perform applications using an interpreter program (e.g. Javascript). A middleware client is a software module that is installed in a device that is configured to request and deliver media or services from a server (e. An example of an embedded application is a navigation browser that is included as part of a television set top box. downloaded applications or virtual applications.

The media player decodes and reformats the incoming media so it can be displayed on the web browser.Chapter 8
Upgradability
Upgradability is the ability of a device or system to be modified. The ability to upgrade the capabilities of a set top box may be performed by software downloads or through the use of software plug-ins. changed or use newer components and/or as technology innovations become available.
End User Device Operation
An IP set top box (IP STB) is an electronic device that adapts a broadband communications signals into a format that can be displayed on a television. The basic functions of an Internet IPTV set top box include selecting and connecting to a broadband connection. The IP STB extracts the IP packets to obtain the transport stream (TS). The channel decoder detects and corrects errors and provides the transport stream to the descrambler assembly.
Media Portability
Media portability is the ability to transfer media from one device to another. separating. decoding and processing media and interfacing the media and controls with the user. Figure 8. This diagram shows that an IP STB typically receives IP packets that are encapsulated in Ethernet packets.
Plug-In
A plug-in is a software program that works with another software application to enhance its capabilities. An example of a plug-in is a media player for a web browser application. The descrambler
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. Media portability can range from stored media locally in a hard disk (for personal video recorder) or by shared media through home connections (such as a premises distribution network).2 shows a functional block diagram of an IP STB.

IPTV Basics

assembly receives key information from either a smart card or from an external conditional access system (e.g. via a return channel). Using the key(s), the STB can decode the transport stream and the program selector can extract the specific program stream that the user has selected. The IP STB then demultiplexes the transport stream to obtain the program information. The program table allows the IP STB to know which streams are for video, audio and other media for that program. The program stream is then divided into its elementary streams (voice, audio and control) which is supplied to a compositor that create the video signal that the television can display.

Figure 8.2, IPTV STB

Network Interface
A network interface is the point of connection between equipment and a communication network. A network interface is the physical and electrical boundary between two separate communication systems. The network interface on set top box may require network selection (if there are multiple networks) and channel selection (if there are multiple channels on a network connection).

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Network Selection
Network selection is the process of identifying and connecting to a network line or system. IP STB may have one or more network connection options that include Ethernet, DSL modem, cable, Wi-Fi, satellite, DTT or other network system. The choice of network connection may include availability of a network signal (is it attached to the network), preferred connection type (higher speed connections) and cost considerations.

Channel Selection
Channel selection is the process of identifying, tuning or adapting and receiving a communication signal. Some networks, such as a cable television network, have multiple channels available on a communication line. For simulcast systems (such as CATV systems), the STB uses a tuner to receive a specific frequency channel.

Return Path
A return path is the medium that is used by information to return to the origin point of the communication signal. IP set top boxes use a return path to permit users to select programs and feature options. The return path may be on the same broadband network that provides IPTV service (e.g. DSL or cable modem) or it may be sent via another path such as a dial-up telephone line.

Demultiplexing
Demultiplexing is a process that separates individual channels from a common transport or transmission channel. STBs perform demultiplexing to separate out logical channels (such as a virtual data channel) and media channels (video, audio and data).

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IPTV Basics

Decoding
Decoding is the process of converting encoded media or data words into its original signal. Decoding involves extracting control signals (e.g. link management) and decrypting the data (if the data has been encrypted).

Rendering
Rendering is the process of converting media into a form that a human can view, hear or sense. An example of rendering is the conversion of a data file into an image that is displayed on a computer monitor. Rendering is performed by decoding the compressed program media (e.g. MPEG) and encoding it into a form that can used by a display (TV) or audio device (speakers).

Video Coding
Video coders convert video media streams or files back into their original or another form. Once the received video is decompressed, it is converted (coded) into a form that can be displayed to the user such as analog video (NTSC or PAL) or digital video (HDMI/DVI).

Audio Coding
Audio coders convert audio media streams or files back into their original (or near original) form. Once the received audio is decompressed, it is converted (coded) into a form that can be played to the user such as analog audio or digital audio (S/PDIF).

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Graphic Processing
Graphics processing is the methods that are used to convert and/or modify image objects from one format into another form. An example of graphics processing the conversion of text into bitmapped images that will be presented onto a display. IPTV systems use graphics processing for navigation menus, alpha blending, and other features such as closed captioning. Alpha blending is the combining of a translucent foreground color with a background color to produce a new blended color. Closed captioning is a service that adds additional information (e.g. text captions) to television programs. Closed captioning information is typically provided by an additional signal that requires a closed captioning decoder to receive and display the captions on the television screen.

User Interface
A user interface is a portion of equipment or operating system that allows the equipment to interact with the user. The user interface includes visual, audio and interface options such as menu screens, program guides, remote controls, control transmitters (IR blasters), web interface, game port and USB accessory ports.

On Screen Display (OSD)
On screen display is the insertion of graphics or images onto the display portion of a screen. The graphics insertion typically occurs at the graphics card or set top box assembly that creates the signals for the display assembly (such as a computer monitor or a television set). The graphics presented by the set top box is created as a display layer that is merged with other display layers such as the background layer and video layer. The graphics display layer may completely overlay the underlying video and background layers or it may be made to be translucent by alpha

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blending. The use of alpha blending allows the viewer to continue to see the programming through the graphic while they view the graphic and make their selections.

Electronic Programming Guide (EPG)
Electronic programming guides are an interface (portal) that allows a customer to preview and select from possible lists of available content media. EPGs can vary from simple program selection guides to interactive filters that dynamically allow the user to search through program guides by theme, time period, or other criteria.

Remote Control
A remote control is a device or system that can be used to control services or a device from a distance. For IPTV set top boxes, remote controls create commands that are used to initiate trick play services. Trick play is the ability of a system to provide for remote control operations during the streaming of a media signal. Trick mode may create a low-resolution display when users scan through a segment of media (such as fast sliding or slow looking).

Wireless Keyboard
A wireless keyboard is a physical device that allows a user to enter data to a computer or other electronic device that is transferred to another device (such as a computer or set top box) via a wireless connection (e.g. radio or infrared).

Infrared Blaster
An infrared blaster is a device that can send (transmit) information on an Infrared carrier signal. IR blasters may be used to by set top boxes to control other accessories (such as tape or DVD players).

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Web Interface
A web interface is the software program that enables a device, system or service to be controlled via a web page or Internet access device. A set top box may have the capability to allow a user to connect to it via a web page to setup operations such as personal video recording times.

Game Port
A game port is a connection that allows for the attaching of joysticks and other interactive devices. Older game ports used a relatively large DB15 connector and new game devices use a standard USB port.

Universal Serial Bus (USB)
Universal serial bus is an industry standard data communication interface. The USB was designed to replace the older UART data communications port. There are two standards for USB. Version 1.1 that permits data transmission speeds up to 12 Mbps and up to 127 devices can share a single USB port. In 2001, USB version 2.0 was released that increases the data transmission rate to 480 Mbps.

Premises Distribution
A premises distribution network is the equipment and software that is used to transfer data and other media in a customer's facility or home. A PDN is used to connect terminals (computers) and media devices (such as TV set top boxes) to each other and to wide area network connections. PDN systems may use wired Ethernet, wireless LAN, powerline, coaxial and phone lines to transfer data or media.

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Interfaces
An interface is a device or circuit that is used to interconnect two pieces of electronic equipment. Interfaces are a boundary or transmission point that is common betweento two or more similar or dissimilar command and control systems.

Network Connections
A network connection is the point of connection between equipment and a communication network. A network connection is the physical and electrical boundary between two separate communication systems.

Ethernet
Ethernet is a packet based transmission protocol that is primarily used in LANs. Ethernet is the common name for the IEEE 802.3 industry specification and it is often characterized by its data transmission rate and type of transmission medium (e.g., twisted pair is T and fiber is F). Ethernet can be provided on twisted pair, coaxial cable, wireless, or fiber cable. Ethernet is a common data connection output connection offered by broadband modems (DSL or cable modems).

Digital Subscriber Line (DSL)
Digital subscriber line is the transmission of digital information, usually on a copper wire pair. Although the transmitted information is in digital form, the transmission medium is an analog carrier signal (or the combination of many analog carrier signals) that is modulated by the digital information signal. DSL data transmission rates range from approximately 1 Mbps to 52 Mbps per line and multiple DSL lines can be combined (bonded) to provide higher combined data rates (100 Mbps+).

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Satellite Connection (Optional)
A satellite connection is a coaxial line that carries satellite RF channels. The frequency of satellite connections is typically above the television frequency band. If a satellite connection if available in the STB, the STB must contain a satellite receiver that can select which satellite RF signal to demodulate and which program channels to demultiplex from the RF carrier channel.

DTT Connection (Optional)
Digital terrestrial television is the broadcasting of digital television signals using surface based (terrestrial) antennas. DTT is also called digital video broadcasting terrestrial (DVB-T).

Cable TV Connection (Optional)
A cable TV connection is a coaxial line that carries RF channels between the set top box and a cable TV system. A cable TV connection requires a tuner to select the RF channel and a channel demultiplexer to separate out the video and audio channels from the RF carrier.

TV RF Output
A TV radio frequency output is a connection point on a television device (such as a STB or DVD player) that provides television signals on an RF channel (such as channel 3 or 4).

Video
Video outputs can be analog or digital form and they can be in component (e.g. color component) form or combined (composite form). A set top box also may contain video inputs can be used to connect webcams for security monitoring or legacy devices such as a VHS tape player

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S-Video
S-video is a set of electrical signals that represent video luminance and color information.3 shows the pin configurations and signal types used on the S-video connectors. The RGB is commonly used for computing devices and the YPbPr are used in television systems. This example shows that the small connector (mini 4 pin) contains a C (chrominance color) video pin #4 and a Y (luminance intensity) video pin #3 and the other two pins are used for a ground (return path) connection.
Component Video
Component video consists of separate signals to represent color.IPTV Basics
Composite Video
Composite video is a single signal that contains all the information necessary to create a video display. Composite video signals are commonly in NTSC or PAL form. Component video may be in various forms including red. The separation of intensity and color information provides for a higher quality video signal than composite video. Figure 8. and blue (RGB) or intensity and color difference signals (YPbPr). green. The standard 7 pin S-Video connector contains a C (chrominance color) video pin #4 and a Y (luminance intensity) video pin #3 along with a tuner control data line pin #6 and a tuner clock control line #5 and the remaining two pins (#1 and #2) are used for a ground (return path)
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The SCART connector does include data lines and switch control lines that allows for the remote powering on of the television and other devices. This diagram shows that the SCART connector has 21 pins – 20 in the
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Figure 8. The connector is designed to allow for cascading (daisy chaining) multiple connectors to each other. The connector primarily is used to provide composite and component video connections between devices.3. Figure 8. S-Video Connector
SCART
A SCART connector is an industry standard interface connector that may be used in television devices to carry video and audio signals.4 shows a diagram of a SCART connector and some of its pin functions. It also includes a control line that allows for the sensing and control of widescreen mode. The connector has 21 pins of which 20 pins are in the center and one pin is the shield of the connector. The SCART connector is also known as the Peritel connector and Euroconnector and the connector is required on consumer devices in some countries (such as France).

composite and S-video signals.4. This diagram shows that the SCART connector can provide component.IPTV Basics
center block and the shield of the connector is a common ground. The specification allows for up to 63 nodes per bus and up to 1023 busses.Link. IEEE 1394 also is known as Firewire or I. The system can be setup in a tree structure. SCART Connector Diagram
IEEE 1394
IEEE 1394 is a personal area network (PAN) data specification that allows for high-speed data transmission (400 Mbps). daisy chain structure or combinations of the two.
Figure 8.
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This diagram shows that the HDMI connector is has 19 pins that are used to carry digital signals and is 13.5.2 Gbps using transition minimized differentiated signaling (TMDS®) balanced lines. HDMI has the ability to determine if security processes are available on the DVI connection and if not.Chapter 8
High Definition Multimedia Interface (HDMI)
HDMI is a specification for the transmission and control of uncompressed digital data and video for computers and high-speed data transmission systems. HDMI is a combination of a digital video interface (DVI) connection along with the security protocol HDCP. HDMI Connector Diagram
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.5 shows an HDMI connector diagram.45 mm high. The HDMI connector has 3 high-speed TDMS® data connections (0.
Figure 8. Figure 8. the HDMI interface will reduce the quality (lower resolution) of the digital video signal. The HDMI connector provides for very high speed data transmission at 10. 1 and 2).9 mm wide by 4.

The use of wireless systems for IPTV distribution offers the advantage of requiring “no new wires.
Sony Philips Digital Interface (S/PDIF)
S/PDIF is a digital audio connection format that allows for the transmission of up to 6 channels of digital audio (5 audio and 1 sub-audio).
Wireless
Wireless connections can be used to provide audio and video signals by radio signals.IPTV Basics
Audio
Audio is a signal that is composed of frequencies that can be created and heard by humans.”
Wireless LAN (WLAN)
A wireless local area network (WLAN) was primary designed to allow computers and workstations to communicate with each other using radio signals.
Baseband Audio
Baseband audio is the fundamental frequency components that contain the information of the audio signal. The frequency range for an audio signal typically ranges from 15 Hz to 20.
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. Audio outputs can be in baseband (analog audio signal form) or in digital form.000 Hz. The common wireless types that are used in set top boxes include wireless LAN and ultra wideband (UWB). There are several versions of WLAN with data transmission rates ranging from 2 Mbps to 54 Mbps. All 6 channels time share a single serial data connection.1 channel surround sound options provided via the digital audio connections. Baseband stereo audio is provided on many STBs with 5.

This may allow the simultaneous operation of UWB transmitters and other existing communication systems with almost undetectable interference. Wi-Fi systems that are used for IPTV multimedia home network may use a combination of 802. a user watching an IPTV stream might have their viewing interrupted when another user is downloading a file over the same Wi-Fi network. Wi-Fi systems that are used for IPTV systems must be able to support quality of service for different types of media. reliable distribution of IPTV signals over consumer-grade Wi-Fi systems have not been possible. keypad controls. This example shows that the visual display shows the selected channel and connection status. Because the UWB signal energy is distributed over a very wide frequency range.6 shows a sample front panel of an IP set top box. This includes interference that may come from other Wi-Fi systems that are operating nearby or microwave ovens or other obstructions that may dynamically appear and cause problem in the transmission of video over Wi-Fi. infrared sensor and an accessory connector.11e quality of service. signal quality levels.Chapter 8
Until recently. The key challenges that face providers and subscribers running IPTV over Wi-Fi is radio signal interference from other sources. In addition to overcome potential interference issues. the interference it causes to other signals operating within the UWB frequency band is extremely small. 802. range and data transmission rates. Wi-Fi is fundamentally an unreliable medium due to that fact that it is shared among multiple users over the unlicensed RF spectrum. Figure 8. This diagram shows that the front panel usually contains a visual display.11n MIMO and smart antenna systems in increase the reliability and performance of the Wi-Fi system.
Ultra Wideband (UWB)
Ultra wideband is a method of transmission that transmits information over a much wider bandwidth (perhaps several GHz) than is required to transmit the information signal. The
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. If it cannot. The use of unlicensed frequency bands can result in interference from other devices that used the same frequency bands (such as microwave ovens and baby monitors).

DTT. The infrared sensor is used to allow a remote control or a wireless keyboard to control the STB.
Figure 8. The audio outputs include left and right audio.7.7 shows a sample rear panel of an IP set top box which contains network connections. video connections. IP STB Real Panel
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Figure 8. menu selection and navigation keys. green and blue). DSL connection.IPTV Basics
keypad controls include power. Satellite and Cable TV. The video options include RF TV out. This example shows that the network connection options include Ethernet connection. component video (red. The accessory connection is a USB connector that allows smart accessories to be connected to the set top box. IP STB Front Panel View
Figure 8.6. audio connections and a smart card socket. Svideo and composite video.

Rights management systems are typically incorporated or integrated with other systems such as content management system. transactional rights and implicit rights. billing systems. Transactional rights are actions or procedures that are authorized to be performed by individuals or companies that granted as the result of a transaction or event. access control and assignment of authorized uses (rights) of content. Rights management systems are typically setup to protect intellectual property and to assist in the valuation and collection of fees for the sale of rights of the intellectual property. Intellectual property is intellect that has been
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. Rights management may involve the control of physical access to information.Chapter 9
Digital Rights Management (DRM)
Rights management is a process of organization. and royalty management. Legal rights are actions that are authorized to be performed by individuals or companies that are specified by governments or agencies of governments. The rights managed by rights management systems can be affected by legal rights. Rights management systems are an implementation of the business and operations aspects of rights management. service authorization. Implicit rights are actions or procedures that are authorized to be performed based on the medium. identity validation (authentication). media protection (encryption) and usage monitoring (enforcement). An example of a transactional right is the authorization to read and use a book after it is purchased in a bookstore. format or type of use of media or a product.

The owner or manager of these property items then assigns rights to specific property items. The rights management system may perform or assist in the collection of license fees or royalties. This diagram shows that a rights management system oversees how content owners can provide access for content to users and how to convert and ensure the usage of content is converted into value for the content owner. Rights Management System
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. transfer and use of the intellect may be protected or restricted. Rights transactions occur when users are given specific rights to use the content.IPTV Basics
converted into some form of value.
Figure 9. Intellectual property may be represented in a variety of forms and the copying. rights transactions. licensing fees and usage monitoring (enforcement). Property in a rights management system requires an identification and description of property items.1. This diagram shows that a rights management system oversees the identification and management of intellectual property items (content).1 shows a rights management system. Figure 9. Various monitoring tools may be used to ensure authorized usage of content and to ensure revenues are collected. rights assignments.

g. Rights may be transferred by the owner of the content or by an agent. When rights are given for the use of content. transferring or manipulating (changing) the intellectual property. audio. a customer buying a book). broadcast) a particular program or service within a geographic area. a licensee is usually the company or person who has been given permission to provide (e. An agent is a person or a device that performs tasks for the benefit of someone or some other device. the rights owner is called a licensee. loan or destroy the book purchased).Chapter 9
The transfer of rights of intellectual property from a content owner to a content user or distributor may involve the use of a formal agreement (e. Royalties are compensation for the assignment or use of intellectual property rights. there is usually some form of tangible compensation defined in license terms such as licensing fees or royalties. A content owner is a person or company that owns the rights to intellectual property (content). processes or takes some form of action on services or products. The types of rights that may be assigned include visual. products or services.
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. company. An agent may be used to assign and transfer rights.g. smell or other forms that can communicate information about intellectual property. A licensor is a company or person who authorizes specific uses or rights for the use of technology. a publishing agreement) or it may occur through an action (e.g. The assignment or transfer of rights may be formalized in a written rights agreement or it may occur as the result of some action such as the purchase of an item (such as the sale of a book) which transfers rights to the owner (such as the right to read. When rights are transferred. A licensee is the holder of license that permits the user to operate a product or use a service. Rights users can be a person. or group that receives. In the television industry. License terms are the specific requirements and processes that must be followed as part of a licensing term agreement. Usage may be in the form of rendering.

Intellectual Property Rights
Intellectual property rights are the privileges (such as exclusive use) for the owner or the assignee of the owner of patents. When the transfer of rights involves the use of content. transport (copy and send) and derive (modify or use portions) for a specific content item. Compulsory licensing usually requires the user of the intellectual property (licensee) to pay the owner (licensor) a reasonable license fee along with non-discriminatory terms. Rights specification defines the ability to render (display). Compulsory licensing is the requirement imposed by a governing body that forces a holder of intellectual property (e. a patent) to allow others to use. it is called a content transaction. the owners of the intellectual property may group together to form a collective licensing system. service or content. copyrights.
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. The specific rights that are assigned during a rights transaction is detailed in a rights specification. A collective licensing system is a process that allows a collective group of technologies or intellectual property to be licensed as a complete group instead of identifying and negotiating licenses for each part separately. and trade secrets. make or sell a product. trademarks. When products require the use of multiple technologies or forms of intellectual property.g.IPTV Basics
Content owners may be able to have exclusive rights to their content restricting its licensing to specific people or companies or content owners may be forced to license specific types of content to various types of users (compulsory licensing). Content transactions can range from simple one time use of content (such as viewing a movie) to the complete transfer of content rights (the sale of content rights to a publisher).

or otherwise distributing the work. music. There may be a time limit between the creation of the work and registration (such as 5 years in the United States). Copyright infringement is the unauthorized use of intellectual property (copyrighted content) by a person or company. Copyrights in many countries can be claimed without registration. art. drama. or any other form of expression . drama. which may be claimed for a limited period of time by the author of an original work of literature.
Patents
A patent is a document that grants a monopoly for a limited time to an invention described and claimed in the body of the document. There are several forms of patents including mechanical patents (processes) and design patents (appearances). However. Registering a copyright is not required and a work may be considered copyright protected when it is initially created (such as in the United States). most countries or regions have a copyright office where copyrights can be officially registered. A patent describes the invention and defines the specific aspects (claims) of the invention that are new and unique. art.Chapter 9
Copyright
A copyright is a monopoly.
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. Copyright protection is the legal rights and/or physical protection mechanisms (security system) that provide control of the use of an original work of literature. Copyright registration does provide additional benefits to the creator or rights holder especially when attempting to enforce copyright protection of the content. or any other form of expression. performing. copying.published or unpublished. Copyrights are Intellectual Property Rights that give the owner or assignee the right to prevent others from reproducing the work or derivates including reproducing. Copyright registration is the process of recording the creation of a new work with the copyright office or intellectual property rights center in the country of origin. music.

which give the owner the right to prevent others from using a similar mark. or selling the invention described and claimed in the patent. using. Copyrights protect original works (creations) from use or performance by others. trademarks.IPTV Basics
To use the technologies described in patents. data. Figure 9. users must obtain patent rights. This diagram shows that rights include patent. In most countries and regions. which could create confusion among consumers as to the source of the goods. Patent rights protect the inventor (or their assignee) from the production or use of their invention by other people or companies. Trademarks protect the use of images or names that they use to promote specific products. design.
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. word. Trademark protection must be registered in the country or region where it is desired. or combination thereof used by firms to identify their own goods and distinguish them from the goods made or sold by others. Most countries have a national patent office and an increasing number of countries grant patents through a single regional patent office. name.2 show the types of intellectual property rights that may be associated with content. Patent rights are intellectual property rights that give the owner or assignee the right to prevent others from making. documents. or anything which has commercial value and which is kept and maintained as confidential. trade secrets and copyright. patents and trademarks are administered by the same government agency. Trademark rights are Intellectual Property Rights. Trade secrets protect the exchanged of private (confidential) information from unauthorized users.
Trade Secrets (Confidential Information)
Trade secrets are information. formulas. An example of a trade secret is a customer list and their service or product purchase histories. brands or services. Patent rights must be applied for in the country or region where they are desired. picture.
Trademarks
A trademark is unique symbol.

Chapter 9

Figure 9.2, Types of Intellectual Property Rights

Types of Rights
The types of rights associated with content include rendering, transporting and modifying (deriving) content.

Rendering Rights
Rendering is process of converting media into a form that a human can view, hear or sense. An example of rendering is the conversion of a data file into an image that is displayed on a computer monitor. Rendering rights as they apply to content include printing, displaying and playing media content. Printing is the rendering of media into a hard copy format. Displaying is the conversion of media into a display format (such as a computer or television display). Playing is the translation of media into an acoustic format.

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Transport Rights
Transport rights are the authorizations to move, copy or loan content. An example of transport rights is the transmission of television programs through a satellite system. Transport rights as they apply to content include moving, copying and loaning content. Moving is the physical transferring of a media file from one location to another. Copying is the selection of a portion or portions of media content and replicating those selections for use or transfer to other people or companies. Loaning is the process of transferring media content to another person or company for a temporary period. Loaning content requires that the original content be removed or disabled from use.

Derivative Rights
Derivative rights are the authorizations to extract, insert or edit content. An example of derivative rights is the use of text from a book or article in a presentation or another article. Derivative rights as they apply to content include extracting, insertion and changing content. Extracting (using sections) is the selection and removal of content for use in another work. Inserting (embedding) is the pasting of additional content (e.g. such as a editorial comment) within an existing content item. Changing (editing) content is the modification of any content or expression of a content item. Figure 9.3 shows basic rights management processes. This example shows that rights management can involve rendering, transferring and derivative rights. Rendering rights may include displaying, printing or listening to media. Transfer rights may include copying, moving or loaning media. Derivative rights can include extraction, inserting (embedding) or editing media.

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Figure 9.3, Rights Management Process

There are many other types of rights that can be associated with content. Publishing rights are the authorized uses that are granted to a publisher to produce, sell and distribute content. Publishing rights may range from global distribution in any media format to specific media formats and geographic areas. Publishing permissions are the rights granted by a publisher for the use of content that the publisher has rights to exercise. Reprint rights are the permissions granted from an owner of content to reprint the content in specific formats (such as reprinting a magazine article). Resale rights are the authorizations that allow a person or company to resell a product, service or content. Resale rights may specify the formats which a product may be sold (e.g. eBook) and where the product may be sold (geographic regions).

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Portability rights are the permissions granted from an owner or distributor of content to transfer the content to other devices (such as from a set top box to a portable video player) and other formats (such as low bit rate versions).

Digital Rights Management
Digital rights management is a system of access control and copy protection used to control the distribution of digital media. DRM involves the control of physical access to information, identity validation (authentication), service authorization, and media protection (encryption). DRM systems are typically incorporated or integrated with other systems such as content management system, billing systems, and royalty management. Some of the key parts of DRM systems include key management, product packaging, user rights management (URM), data encryption, product fulfillment and product monitoring. When intellectual property is stored in a form of digital media, objects of value are called digital assets. Digital assets have rights associated with them and digital right management systems oversee how the rights are transferred between owners and users of digital assets. Content owners who want to protect their content as it is distributed through television systems may require the use of DRM. Content owners (such as studios) may prefer to use or endorse specific types of DRM systems. A studio endorsement is the allowance of the use of a program or service as long as the use meets with specific distribution requirements. Studios may endorse (authorize) or prefer the use of specific content protection systems that can be used for the distribution of their programs and not all content protection systems meet their security requirements. Media service providers who do not use a studio endorsed content protection system may not be able to get and distribute content from some studios.

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Rights Attributes
Rights attributes are the details related with each right associated with a content item. An example of a rights attribute is the authorization to print a version of an eBook up to 3 times for a university professor. Common types of rights attributes include permissions, extents and consideration. Permissions Rights permission is the uses or authorizations to perform actions on or concerning the use of content. Permissions include reproduction (copying), deriving (modifying), transporting (distributing), performing or displaying (rendering) the work. Rights Extents Rights extents are the amount of usage of a content item that is authorized. Rights extents may be defined in units of time, the number of uses and what places (geographic regions) that the rights apply. Rights Consideration Rights consideration is the authorization or transfer of value in return for the assignment of rights. Rights consideration may be in the form of money or any other quantifiable items or services. Rights consideration may be a combination of royalties, commissions, grants of license fees.

Rights Models
Rights model is a representation of how the content rights are transferred and managed between the creator or owner of content and the users or consumers of content. Examples of rights models include a radio broadcasting rights model, television-broadcasting rights model, Internet rights model and a book rights model.

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Radio Broadcasting Rights Model
A radio broadcasting rights model defines how the audio media content (such as music programs) is transferred to listeners (users). The radio broadcasting rights model may start with the music content production company (e.g. recording company), which makes a production agreement with a music artist. This allows the recording company to produce and sell the music in a variety of formats in return for paying a percentage of sales (royalties) back to the music artist. As part of the radio broadcasting rights, radio broadcasting stations sign licensing agreements with record companies or their authorized agents (associations) which allow them to broadcast the music on radio channels to listeners. The fees paid for radio broadcasting rights vary depending on the location and number of listeners the radio station has. As part of the licensing agreement, users may listen to the music and have rights to store (record) and replay the music with certain usage restrictions. The radio broadcasting company typically receives its compensation for broadcasting from advertisers. Figure 9.4 shows a rights model that represents music from its creation to a radio listener. This example shows how a musician signs a contract with a recording company that allows for the creation and sale of music CDs and DVDs. The recording company signs a licensing contract with a radio station that allows the music to be played on the airwaves. The listener can enjoy the music with certain usage restrictions. The radio broadcasting company pays licensing fees to the recording company, which pays a portion of this money to the musician in the form of royalties.

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Figure 9.4, Radio Broadcast Rights Transactions

Television Broadcasting Rights Model
A television broadcasting rights model defines how the video and audio content (such as a television program) is transferred to viewers (users). The television broadcasting rights model may start with the program content production company (e.g. movie studio), which makes production agreements with a variety of artists (e.g. actors and directors). This allows the movie studio to produce and sell the program in a variety of formats in return for paying fees and potentially a percentage of sales (royalties) back to the artist. As part of the television broadcasting rights, television broadcasting stations, cable television companies or other television program distributors sign licensing agreements with movie studio or their authorized agents (content aggregators) that allow them to broadcast the television programs on their distribution systems to viewers. The fees paid for television broad-

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IPTV Basics

casting rights vary depending on the location and number of viewers the television broadcaster has. As part of the licensing agreement, users may view and have rights to store (record) and replay the television programs with certain usage restrictions. The television broadcasting company may receive its compensation for broadcasting from subscription (e.g. monthly subscription service fees), usage (e.g. pay per view) and advertising fees. Figure 9.5 shows a rights model that represents television media from the creation of television shows to rights of a TV viewer. This example shows how a production studio signs contracts with actors, graphics artists and writers to product television content. Each of these content developers and providers provide broadcasting rights (and possibly other rights) to the movie studio. The production company signs a licensing agreement with a broadcast company that allows the media to be sent via television radio broadcast, cable transmission or via satellite systems. The viewer is allowed to view and store the television program for his or her own personal use. The broadcaster receives subscription and/or pay per view fees from the viewer,

Figure 9.5, Television Rights Transactions

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Web users obtain user rights when they connect to the web host and transfer media to their computer. product help screens) or through the insertion and viewing of advertising messages (e. royalties and potentially other contributions to artist guilds (e. The Internet rights model may start with a person or business that wishes to combine content into a form that can be communicated to viewers who connect to their web site through a public network (the Internet).g. As part of the licensing agreement. photographers and recording artist to provide media components. The web development signs an agreement with a web hosting company which requires the web developer to have all the rights necessary to transfer the content to users.g. The person who combines the content into a format that is provided by the web site is called a webmaster. Figure 9. companies or creators may own the content that is combined on a web site.Chapter 9
the production studio receives license fees from the broadcaster for distribution (possibly revenue sharing) and the contributing artists receive performance fees. The company that manages the content on the web site may make money through the sale of products. users may view and have rights to store (save) and transfer the media captured from the web site. Multiple people. reduced cost of supporting product sales (e. Each of these content providers and developers provide web casting rights (and possibly all other rights) to the web site developer. This example shows how a web developer obtains content or developer agreements with videographers. banner ads). actors guild) and associations. The webmaster is usually responsible for ensuring that only authorized information is stored and provided on the web site.6 shows a rights model that represents how content may be created and hosted on the Internet and access by a web user.g. This example shows that these rights may
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.
Internet Rights Model
An Internet rights model defines how the multimedia content (such as a web page) are transferred to Internet viewers (users).

IPTV Basics
include viewing. and storing the media on their personal computer. The web developer then receives development fees from the web host and the content providers receive licensing fees and/or royalties from the web developer. forwarding.g.
Figure 9. The web host receives compensation from the web user in the form of page visits and/or link clicks (which may be paid for by another company). Metadata is information (data) that describes the attrib-
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. applications) or information content (e.6. software (e. Internet Rights Transactions
Digital Assets
A digital asset is a digital file or data that represents a valuable form of media. media programs). printing. Digital content is raw media (essence) that is combined with descriptive elements (metadata).g. Digital assets may be in the form of media files.

Some of the key types of digital assets include digital audio. Digital assets are typically stored in a high-resolution version so they that can be converted (transcoded) into lower resolution formats as required. videodisks) that is protected by a password system and data network firewalls.
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. digital assets may be combined to create new digital assets through the production and editing process. Javascript files). This process produces secondary content. scripted programs (e. video. Metadata or Meta tags are commonly used to provide technical and descriptive information about other data. A television program may contain technical metadata that describes the media encoding formats and duration of the media along with descriptive metadata that provides information about the title and actors.Chapter 9
utes of other data. In addition to digital assets that may be acquired or originally recorded (such as video from a sports game). (Metadata is data that describes other data).g. processing. fonts and other types of media that can be represented in digital form.
Digital Audio (Voice and Music)
Digital audio is the representation of audio information in digital (discrete level) formats. animation and application programs.g. The use of digital audio allows for more simple storage. An example of secondary content is the creation of “sports highlights” from a series of games that were previously broadcasted. images. There can be many other types of digital assets including web pages. This vault may be an electronic storage facility (e. The original digital assets (master files) are commonly stored in a secure area (called a “vault”) which usually has restrictions on use or have usage costs associated with the content. and transmission of audio signals. High-resolution digital assets require an extensive amount of storage area so older or less used digital assets are commonly moved to offline repositories.

media coders are only capable of transforming signals of the media types they are designed for. Waveform coding consists of an analog to digital converter and data compression circuit that converts analog waveform signal into digital signals that represent the waveform shapes. Audio fidelity is the degree to which a system or a portion of a system accurately reproduces at its output the essential characteristics of the signal impressed upon its input. However. Media coders typically provide a substantial amount of compression (8:1 ore more). Perceptual coding can take advantage of the inability of human senses to capture specific types of information.5 Mbps (for 2 channels of audio). The typical data transmission rate for uncompressed high quality audio is 1. speech coding analyzes the analog signal into codes that represent human sounds. the human ear cannot simultaneously hear loud sounds at one tone (frequency) and soft sounds at
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. media or perceptual coding. Digital audio is commonly compressed (coded) to reduce the amount of storage that is required for the audio. The conversion process determines the fidelity of the digital audio signal. MP3) at 128 kbps. For example. This is why music does not typically sound good through mobile telephones as mobile telephones compress human audio and they are not designed to compress the sounds of musical instruments. Perceptual coding is the process of converting information into a format that matches the human senses ability to perceive or capture the information. There key ways that digital audio may be coded including waveform coding. Media coding is the process of converting an analog waveform into components that represent its underlying media format.g. This requires a data storage area of approximately 11 MBytes for each minute of storage.IPTV Basics
The creation of digital audio typically involves the conversion of analog signals into digital formats (it is possible to create synthetic audio without analog signals). Waveform coders are capable of compressing and decompressing voice audio and other complex signals. Broadcast audio is commonly compressed and transmitted in an MPEG format (e. For example.

MP3 coding format uses perceptual coding.g. gaming applications). Animation can be a change in position of an image within a video frame to synthetically created images that change as a result of programming commands. it is not necessary to send signals that cannot be heard even if the original signal contained multiple signals. scanning or digital photographing) or it may be through the creation of digital components (image editing).g.Chapter 9
another tone (different frequency). The number of pixels per unit of area determines the resolution of the image. A display with a finer grid contains more pixels. The production of animated images may be performed at the broadcaster’s facility or they may be performed at the viewer’s location (e.
Animation
Animation is a process that changes parameters or features of an image or object over time.
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. The raw file size is determined by how many bits represent each pixel of information. A single image that has high resolution can require over 200 MBytes per image (600 dpi x 11” horizontal x 600 dpi x 17” vertical x 24 bits (3 Bytes) per pixel = 200+ MBytes). The creation of digital images may involve the conversion of pictures or images into digital format (e.g. therefore it has a higher resolution capable of reproducing more detail in an image. Images may be used within or added to (e. logos) program materials. Animation media is the set of data and images along with their controlling software commands that are used to produce animated displays.
Images
Images are data files that organize their digital information in a format that can be used to recreate a graphic image when the image file is received and decoded by an appropriate graphics application. Using perceptual coding.

This requires a data storage area of approximately 200 MBytes for each minute of standard definition storage and more than 11 GBytes for 1 minute of high definition television storage.
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. image or section of information.5 Gbps. Broadcast video is commonly compressed and transmitted in an MPEG format at 2 to 4 Mbps (2 hours of video is approximately 4 GBytes = 1 DVD). the use of compression is minimized to ensure the quality of the original materials. Digital video is commonly compressed (coded) to reduce the amount of storage that is required for the video.IPTV Basics
Digital Video
Digital video is a sequence of picture signals (frames) that are represented by binary data (bits) that describe a finite set of color and luminance levels. the data transmission rate for digital video can be reduced by 200:1 or more. The ways that digital video may be coded (compressed) including spatial compression and temporal compression. During the editing and production process. Temporal compression (between frames) is the analysis and compression of information or data over a sequence of frames. The digital information contains characteristics of the video signal and the position (or relative position) of the image (bit location) that will be displayed. Sending a digital video picture involves the conversion of a scanned image to digital information that is transferred to a digital video receiver. Combining spatial compression and temporal compress. Spatial compression (within a frame) is the analysis and compression of information or data within a single frame. The typical data transmission rate for uncompressed standard definition (SD) television is 270 Mbps and uncompressed high definition (HD) digital video is approximately 1. images or sections of information.

word processing programs and spreadsheets.Chapter 9
Data Files (Books and Databases)
A data file is a group of information elements (such as digital bits) that are formatted (structured) in such as way to represent information. A container may hold descriptors (metadata). Each component also has a descriptor that provides specific information about its resources (e. Figure 9. This example shows that each item has a descriptor that provides details about its components.
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. Contain files hold items that contain raw data (essence) and descriptions (metadata). a data file can contain any type of information such as text files or electronic books. digital video). Items within a container file may contain other items.
Application Program Files (Software Applications)
An application program is a data file or group of data files that are designed to perform operations using commands or information from other sources (such as a user at a keyboard). This diagram shows a container that is composed of 3 main items and one of the items contains an item within itself. Some applications (such as embedded program applications) do not involve regular human interaction such as automotive ignition control systems.7 shows how a file container can hold multiple media items (components) and how each item has a description. raw media). indexes and/or raw media objects (e. Popular applications that involve human interface include electronic mail programs.g.
Container Files
A container is a structured format of a media file that can hold a group of items.g. While the term data file is commonly associated with databases (tables of data).

In addition to holding the raw media in a format that can be used by production people. video and audio) are re-assembled into their original media format.IPTV Basics
Figure 9. the material exchange format (MXF) format may be used. the AAF structure includes additional information that can assist in the production (authoring) process.
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. The metadata within the MXF media format describes how the media elements (e. Editing and production may use the advanced authoring format (AAF) to hold digital media (essence and metadata).7. Media file Container
There are various container file formats that are used to hold content for the television industry. When creating content segments for broadcast programs. MXF is a limited version (subset) of the AAF structure.g.

This information may be technical or descriptive data. some media may be ingested slowly to allow for the user of slower.
Ingestion
Ingesting content is a process for which content is acquired and loaded onto initial video servers (ingest servers). tapes) or data connections. Content ingestion may come from several different sources including satellite downlinks. categorized and stored with the digital asset. and distributing (broadcasting and transferring) digital assets. The first step in cataloging is labeling (logging) the digital asset when it is acquired or created. it is identified (labeled) along with key characteristics and added to the catalog of materials. In general. additional information is associated with the digital asset. As media is ingested into a DAM system. The cataloging process is becoming more automated and much of the metadata that is already provided with the media may be automatically imported. After the digital asset is identified. While ingestion may be directly controlled from media players (such as DVD players). the cost of the data connection dramatically increases. low cost data connections. stored media (DVDs.Chapter 9
Digital Asset Management (DAM)
Digital asset management is the process of acquiring (ingesting). maintaining (managing assets).
Cataloging
Cataloging is the process of identifying media and selecting groups of items to form a catalog or index of the stored media. As a result. some content is transferred via data networks and there is a cost associated with the transfer of information through these networks. To ensure that descriptions
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. Cataloging is a key part of the asset manager. as the data connection speed and distance increases. Much of this information may already be available within the metadata portion of the asset that is ingested.

program editors identify content segments to use and the starting and ending points in these segments by developing and edit decision list (EDL). The EDL may be created using an off-line editing system. digital assets may be stored in remote nearline or offline storage systems that require some time to find. metadata industry standards such as MPEG7 are being developed.
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. RAM). To create a program. not to confuse the category of thriller with pornography). select and prepare access to the media. The media only needs to be accessible when the EDL is processed to create the final master video program. connection. An EDL is a set of records that contain the names of media files and time position locations within these files (edit in-points and out-points) that are used to create a video program. Assets that are directly accessible to users and devices connected to the media system are called online assets.IPTV Basics
are clear and compatible between networks (e. The media that is referenced in an EDL list does not have to be available during its creation.g. Because direct and fast online storage is relatively expensive. Some of the common types of digital storage mediums include electronic (e.g.
Digital Asset Storage
Digital asset storage is a process of transferring data into or onto a storage medium (a repository) in which information can be retained.
Editing and Production
Editing and production is the searching. tape or hard disk) and optical (e. CDROM or DVD). Repositories may be immediately accessible (such as video servers) or the storage media may need to be selected and loaded (such as videodisks). magnetic (e. and combining of media materials to produce programs or contents segments.g.g. selection. Nearline assets are files or data that represents a valuable form of media that are not immediately available for use but can be made available for use in a short period of time. Offline assets are files or data that represents a valuable form of media that is not directly or immediately available for use.

scheduled or on demand delivery. Scheduled programs may be transmitted at a slower transmission rate to reduce the costs of data transmission.8 shows a digital asset management system.Chapter 9
Playout and Distribution
Once content is ingested it can be edited to add commercials. The distribution of content may be in real time. This example shows that content may be ingested from a variety of sources including live feeds or analog and digital stored media formats. This example shows that the asset manager creates and uses catalog information to allow the system and users to find. The distribution portion is responsible for transferring assets to broadcast (real time). This diagrams shows that the basic functions for a digital asset management system include ingestion. organize and obtain media. This delivery schedule may occur several hours before the program is scheduled to be broadcasted to customers. cataloging and distribution. Some asset management systems allow broadcasters to connect to the asset management system and download the materials when they require them (or when they can cost effectively transfer them). nearline and offline repositories and coordinating the conversion (transcoding) of media into other formats (such as MPEG). migrated to a playout server or played directly into the transmission chain. The asset manager coordinates the storage and retrieval of media into online (cache). other storage systems (time delayed) and/or to Internet streams
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. Figure 9. New content may also be created through the editing and production of existing assets. through scheduled or on demand delivery. Playout is the process of streaming or transferring media to a user or distributor of the media. Playout may be in the form of real time broadcasting. Real time broadcasting involves directly converting (transcoding) media into a format that can be transferred through a distribution network such as a direct to home (DTH) satellite or cable television system. Prerecorded media may be scheduled for delivery to networks or other distribution systems.

DOI (multimedia) and watermarks.8. The UMID standard was adopted as SMPTE standard 330M.
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. The basic UMID contains 32 bytes of information and the first 12 bytes are used as a label to indicate that the media has a UMID code.
Unique Material Identifier (UMID)
A unique material identifier is a unique code that is used to identify audiovisual (AV) materials. Some of the common identification codes that may be assigned to digital media include UMID. ISBN (books).IPTV Basics
Figure 9. Bytes 13 through 15 define the length of the material and the last 16 bytes of the UMID are a unique number that identifies the specific content item. ISSN (magazines). Digital Asset Management System
Media Identification
Digital media content must be uniquely identified.

language or geographic area. and a calculated check digit to ensure an ISBN has been entered correctly into a computer or system. along with some additional user information. time and location where the content originated.
Figure 9.
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. title identifier.Chapter 9
A UMID can be extended with another 32 bytes of content descriptive information to create an extended UMID (EUMID). the place (location) that the media was created. Figure 9. The EUMID contains the date.9 shows the structure of an EUMID identifier. This diagram shows that an EUMID is composed of the basic 32 byte UMID that contains the media identification information plus additional 32 bytes of descriptive information.9. EUMID Identifier
International Standard Book Number (ISBN)
An international standard book number is a unique number assigned to a specific book. This additional descriptive information includes the data and time the media was created. publisher. The ISBN identifies the issuing group.

Once a DOI is created. a book identification number may belong to the original publisher until the copyright of the work is sold to another publisher. the owners of the item content changes. it is considered permanent and is not deleted.g.DOI. The use of a DOI directory as a locating mechanism allows for the redirecting of information about identification information as changes occur in its identifying characteristics. DOI numbers perform for long term (persistent) and locatable (actionable) identification information for specific content or elements of content. The numbering structure (syntax) for a DOI includes a directory and owner part (prefix) and unique item identification number (suffix). For example. This content can be in the form of bar codes (price codes). More information about DOI numbering can be found at www. book or magazine identification numbers or software programs.IPTV Basics
International Standard Serial Number (ISSN)
An international standard serial number is a unique number that identifies the particular issue of a series of magazines or periodical publications.
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. At this time. While the ISSN identifies the series publication. DOI numbers point to a DOI directory that is linked to specific information about a particular object or its information elements.org. the particular issue (e. The DOI system is managed by the International DOI foundation (IDF) that was established in 1998. volume or issue) has the series idefined by the publisher and it is not part of the ISSN. The ISSN number contains a unique portion that identifies the particular series of publication and a check digit to ensure an ISBN has been entered correctly into a computer or system. This redirection may be to a URL web link.
Digital Object Identifier (DOI)
A digital object identifier is a unique number that can be used to identify any type or portion of content. The item number on the book can remain the same while the publisher information can change. The prefix allows the DOI directory to redirect (DOI resolution) identification information to the owner or controller of the identifiable item.

Figure 9.10 shows digital object identifier (DOI) structure.10.
Figure 9.
International Standard Audiovisual Number (ISAN)
International standard audiovisual number is a unique code that is approved by the International Standard Organization (ISO) in standard
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. This example shows that a DOI number is composed of a prefix that is assigned by the registration agency (RA) of the international DOI foundation and suffix that is assigned by the publisher of the content. a book can have a DOI. For example. DOI Structure
International Standard Recording Code (ISRC)
The international standard recording code is a unique code that is approved by the International Standard Organization (ISO) to identify audio-visual (AV) recorded materials. Each ISRC code is unique and permanently stored within the recorded media program. a single object may have different types of identification numbers assigned to it. This example shows that the first part of the prefix identifies the DOI directory that will be used and the second part identifies the publisher of the content.Chapter 9
While it is important that there be only one DOI assigned per content object. international standard book number (ISBN) and a manufacturers product number assigned to it.

DRM systems are designed to establish and maintain security associations between two network elements that ensures that traffic passing through the interface is cryptographically secure (typically.IPTV Basics
15706 to identify AV materials or portions of AV materials. through the use of encryption). digital signatures.
International Standard Work Code (ISWC)
International standard work code is a unique code that is approved by the International Standard Organization (ISO) in standard 15707 to identify materials or portions of materials for the music industry. digital fingerprints. This validation
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.
DRM Security Processes
Security is the ability of a person.
Authentication
Authentication is a process of exchanging information between a communications device (typically a user device such as a mobile phone or computing device) and a communications network that allows the carrier or network operator to confirm the true identity of the user (or device). The International ISAN Agency maintains and coordinates a centralized database of all ISAN records. authentication and encryption to provide security assurances to media content and their delivery systems. product activation codes. DRM systems are designed to protect the rights of the media owners while enabling access and distribution of the media programs to users. theft or compromise of its resources from unwanted people or events. conditional access systems. The International ISWC Agency maintains and coordinates a centralized database of all ISWC records. system or service to maintain its desired well being or operation without damage. digital certificates. DRM systems can use a combination of digital watermarks.

Thus. A common way to create identification codes that cannot be decoded is through the use of password hashing. authentication inhibits fraudulent use of a communication device that does not contain the proper identification information. a hash code is created from the password 542678. company or device.11 shows how hashing security can be used to create identification codes that cannot be directly converted back into the original form.11. Figure 9. Password Hashing
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. service access codes and secret keys. In this example. Password hashing is a one way encryption process as it is not possible to derive the original password from the hashed code. The hashing
Figure 9. Authentication credentials are the information elements that are used to identify and validate the identity of a person.Chapter 9
of the authenticity of the user or device allows a service provider to deny service to users that cannot be identified. Authentication credentials may include identification codes. Password hashing is a computational processes that converting a password or information element into a fixed length code.

The DRM system has previously sent a secret key to the user. This random number is used by the receiving device and is processed with the secret key with an authentication (data processing) algorithm to produce a calculated result. In this diagram. This result is sent to the originator (authenticator). adding the even digits to calculate a result (18) and then storing the results of the password (1418).IPTV Basics
process involves adding the odd digits to calculate the result (14). Figure 9. If the result received from the remote device with its own result matches. Note that the secret key is not sent through the communication network and that the result will change each time the random number changes. the authentication passes.
Figure 9. a DRM server wants to validate the identity of a user. the original password cannot be recreated from the hashing results. The originator uses the random number it sent along with its secret key to calculate a result. By using this hashing process.12 shows a typical authentication process used in a DRM system. Authentication Operation
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. The authentication process begins with the DRM server sending an authentication request and a random number. even if you know the hashing process.12.

this example shows that the original information becomes unrecognizable by the typical viewer. Encryption involves the use of a data processing algorithm (formula program) that uses one or more secret keys that both the sender and receiver of the information use to encrypt and decrypt the information. Figure 9.the letter I becomes the letter J).
Figure 9.13. Without the encryption algorithm and key(s). unauthorized listeners cannot decode the message. the letters in the original information are shifted up by 1 letter (example .Chapter 9
Encryption
Encryption is a process of a protecting voice or data information from being used or interpreted by unauthorized recipients. In this example.13 shows the basic process used by encryption to modify data to an unrecognizable form. With this simple encryption. Basic Encryption Process
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.

Figure 9.14. An encryption key is generally kept private or secret from other users. The encryption key length is the number of digits or information elements (such as digital bits) that are used in an encryption (data privacy protection) process.14 shows how encryption can convert non-secure information (cleartext) into a format (cyphertext) that is difficult or impossible for a
Figure 9. the longer the key length. Encryption systems may use the same encryption key to encrypt and decrypt information (symmetrical encryption) or the system may use different keys to encrypt and decrypt (asymmetrical encryption). Generally. Information that has not been encrypted is called cleartext and information that has been encrypted is called ciphertext. Encryption Operation
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. An encryption key is a unique code that is used to modify (encrypt) data to protect it from unauthorized access.IPTV Basics
Encryption Keys
An encryption system typically uses a combination of a key (or keys) and encryption process (algorithm) to modify the data. the stronger the encryption protection.

Chapter 9
recipient to understand without the proper decoding keys.
Figure 9. data is provided to an encryption processing assembly that modifies the data signal using an encryption key.
Symmetric and Asymmetric Encryption
Encryption systems may use the same key for encryption and decryption (symmetric encryption) or different keys (asymmetric encryption).15. to setup and perform encryption between com-
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. a public key and a private key.15 shows the differences between symmetric and asymmetric encryption. Symmetric and Asymmetric Encryption Processes
Public Key Encryption
The encryption process may be private or public. Generally. In this example. asymmetric encryption requires more data processing than symmetric encryption. This diagram shows that symmetrical encryption uses the same keys to encrypt and decrypt data and that asymmetric encryption uses different keys and processes to encrypt and decrypt the data. Figure 9. This diagram also shows that additional (optional) information such as a frame count or random number may be used along with the encryption key to provide better information encryption protection. Public key encryption is an asymmetric authentication and encryption process that uses two keys.

The public key is a cryptographic key that is used to decode information that was encrypted with its associated private key.405.
Pretty Good Privacy (PGP)
Pretty good privacy is an open source public-key encryption and certificate program that is used to provide enhanced security for data communication. The RSA algorithm was patented in 1983 (patent number 4.
Rivest.g.829). AES. encryption) applied to it. The use of blocked encryption may make re-synchronization easier which may occur if there are transmission errors. The public key and private keys can be combined to increase the key length provider and more secure encryption system. RSA. It was originally written by Phil Zimmermann and it uses Diffie-Hellman public-key algorithms. The public key can be made available to other people and the owner of the key pair only uses the private key. The RSA encryption process encodes the data by raising the number to a predetermined power that is associated with the receiver. RC5 and ISMACrypt. The encryption process may be continuous or it may be based on specific sections or blocks of data. Shamir and Aldeman (RSA)
Rivest. The RSA algorithm is an encryption process that is owned by RSA Security. Inc. There are several types of encryption processes used in DRM systems including PGP. Shamir and Adleman is a public key encryption algorithm named after its three inventors.IPTV Basics
munication devices. DES.
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. A media block is a portion of a media file or stream that has specific rules or processes (e. divided the number by predetermined prime numbers that are also associated with the receiver and transferring the remainder (residue) as the ciphertext.

The AES standard is supposed to replace the Data Encryption Standard (DES).
Rivest Cipher (RC5)
RC5 is a symmetric block encryption algorithm that was developed by the expert cryptographer Ronald L. 64 or 128 bits and can use a key size that can range from 0 to 2040 bits. efficient encryption process that can use variable block sizes and key lengths.Chapter 9
Data Encryption Standard (DES)
The data encryption standard is an encryption algorithm that is available in the public domain and was accepted as a federal standard in 1976.
International Streaming Media Association (ISMACrypt)
International streaming media association encryption is a privacy coding process that was developed by the ISMA for streaming applications.
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. The RC5 encryption process has block sizes of 32.
Advanced Encryption Standard (AES)
Advanced encryption standard (AES) is a block data encryption standard promoted by the United States government and based on the Rijndael encryption algorithm. 128. RC5 is a relatively simple. transpositions and nonlinear mathematical operations. 192 or 256 bits. The AES system uses a fixed block size of 128 bits and can have key sizes of. Triple data encryption standard (3DES) is a variation of the data encryption standard that adds complexity to the encryption process by increasing the difficulty to break the encryption process. It encrypts information in 16 stages of substitutions. Rivast.

a digital watermark should not be distorted or lost when the signal is passed through a conversion or compression process. For example. the signal altered so that the hidden information could no longer be determined) by any imperceptible processing of the overall signal.16 shows how watermarks can be added to a variety of media types to provide identification information. Figure 9. Encrypted watermarks are tamper resistant information that is added (data embedding) or changed information in a file or other form of media that can be used to identify that the media is authentic or to provide other information about the media such as its creator or authorized usage. A software program or assembly that can separate the watermark from a media file extracts a digital watermark. Digital watermarks can be added to any type of media files such as digital video and audio. Ideally a digital watermark would not be destroyed (that is. a decryption code is needed to decipher the contents of the watermark message. The process of watermarking is called stenography. Watermarks can be encrypted to increase the resistance of the DRM system to hackers. This watermark may be used to provide the key that is able to decode and play the media file. This example shows that digital watermarks can be added to digital audio or video media by making minor
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. Audio watermarking may be performed by adding audio tones above the normal frequency or by modifying the frequencies and volume level of the audio in such a way that the listener does not notice the watermarking information.IPTV Basics
Digital Watermarks
A digital watermark is a signal or code that is hidden (typically is imperceptible to the user) in a digital signal (such as in the digital audio or a digital image portion) that contains identifying information. While it may be possible to identify the watermark in the media file. Adding or slightly modifying the colors and/or light intensities in the video in such a way that the viewer does not notice the watermarking information may perform video watermarking.

high frequency sound) or video components (color shift) that cannot be perceived by the listener or viewer.16. The digital watermark is added as a code that is typically not perceivable to the listener or viewer of the media.g.
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. This example shows that digital watermarks can be added to audio signals in the form of audio components (e.
Digital Fingerprint
A digital fingerprint is a unique set of characteristics and data that is associated with a particular data file. Digital fingerprints may be codes that are uniquely embedded in a media file or they may be unique characteristics that can be identified in the storage or transmission medium such as the particular variance of digital bits that are stored on a DVD.Chapter 9
Figure 9. Digital Watermarking Operation
changes to the media content. transmission system or storage medium.

Trusted third parties that issue digital certificates are called a certificate authority (CA). A trusted third party is a person or company that is recognized by two (or more) parties to a transaction (such as an online) as a credible or reliable entity who will ensure a transaction or process is performed as both parties have agreed. The CA maintains records of the certificates that it has issued in repositories and these records allow the real time validation of certificates. the user can trust the certificate and use the public key provided by the content owner (such as an online store). they have an implied trusted relationship with each other. the certificate can be revoked. Because the user can validate the signature on the certificate using the CA’s public key. Certificates are usually created or validated by a trusted third party that guarantees or assures that the information contained within the certificate is valid. the content owner sends their public key that is in the signed certificate. This diagram shows that because the content owner and content user both exchange identification information with the CA. The CA typically requires specific types of information to be exchanged with each party to validate their identity before issuing a certificate. The content user registers with the CA and receives a certificate from the CA.17 shows how digital certificates can be used to validate the identity of a provider of content. Figure 9. The content owner registers with the CA and receives a key pair and a certificate signed by the CA. When the user requests information from a content owner. This diagram shows that users of digital certificates have a common trusted bond with a certificate authority (CA). If the certificate information is compromised.IPTV Basics
Digital Certificate
A digital certificate is information that is encapsulated in a file or media stream that identifies that a specific person or device has originated the media.
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.

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. the media file is processed using a certificate or validated identifying information using a known encoding (encryption) process. To create a digital signature. The media file and the signature are sent to the recipient who separates the signature from the media file and decodes the key using the known decoding (decryption) process. Digital Certificate Operation
Digital Signature
A digital signature is a number that is calculated from the contents of a file or message using a private key and appended or embedded within the file or message.17. This produces a unique key that could only have been created using the original media file and identifying certificate.Chapter 9
Figure 9. The inclusion of a digital signature allows a recipient to check the validity of file or data by decoding the signature to verify the identity of the sender.

and terminations of subscribers of a service. changes. Some of these characteristics may include the combination of a processor type.
Machine Binding
Machine binding is the process of linking media or programs to unique information that is located within a computer or machine so the media or programs can only be used by that machine. SHTTP is designed to privately send and receive messages without the need to setup and maintain a security session. CA systems use a subscriber management system coordinates the additions. Conditional access systems can use uniquely identifiable devices (sealed with serial numbers) and may use smart cards to store and access secret codes. user keypad) or via an external connection (downloading the
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. the date the operating system was first installed and the memory storage capacity of other key characteristics that are unlikely to change over time.
Conditional Access (CA)
Conditional access is a control process that is used in a communication system (such as a broadcast television system) that limits the access of media or services to authorized users. It controls and manages communications between a Web browser and a Web server.
Product Activation
Product activation is the process of enabling a product to begin operation by entering information into the product through the use of either local operations (e.g.IPTV Basics
Secure Hypertext Transfer Protocol (S-HTTP)
Secure hypertext transfer protocol is a secure version of HTTP protocol that is used to transmit hypertext documents through the Internet.

The SSL process uses certificates from trusted third parties (certificate authorities) that validate the authenticity of messages and users. SSL version 2 provides security by allowing applications to encrypt data that goes from a client. which allows the user to decode encrypted messages that are provided by the vendor. The server (vendor) provides their public key in their certificate. The owner of the key pair only uses the private key and the public key can be shared with others. This diagram shows that SSL operation uses asymmetric public key encryption to allow the sharing of public keys and that a certificate authority is used as a trusted third party to provide public keys that are accessible and verifiable.
Secure Socket Layer (SSL)
A secure socket layer (SSL) is a security protocol that is used to protect/encrypt information that is sent between end user (client) and a server so that eavesdroppers (such as sniffers on a router) cannot understand (cannot decode) the data. Because the asymmetric encryption process used by the SSL system is relatively complex and time consuming to process.18 shows how secure socket layer can be used to protect the transfer of digital information between the user (client) and the provider (server) of the information. SSL version 3 allows the server to authenticate (validate the authenticity) the client. Product activation usually requires that certain customer financial criteria must also be met before the product activation is performed or before the necessary product entry information is provided to the customer. SSL uses a public asymmetric encryption process that uses a key pair. to a matching server (encrypting your data means converting it to a secret code). In this example. the CA has provides a key pair (public and private key) to a vendor. The vendor certificate is signed
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. such as a Web browser.Chapter 9
information into the product). One key is private and one key is public. Figure 9. the SSL system may change its encryption process to use symmetric encryption after the initial asymmetric public key secure link has been setup.

This example shows that after SSL public key encryption link is established.
Transport Layer Security (TLS)
Transport layer security is a set of commands and processes that are used to ensure data transferred across a connection is private.IPTV Basics
Figure 9. Secure Socket Layer (SSL) Operation
by the CA. TLS record protocol and TLS handshake protocol. programs and hardware that facilitate the assignment. TLS is the evolution of secure socket layer (SSL) protocol that was developed by Netscape. TLS is composed of two protocol layers. management and enforcement of the rights asso-
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DRM System
DRM systems are a combination of processes. which can be verified by the user.18. TLS is defined in RFC 4346. the SSL system can exchange keys that can be used for a less complex symmetrical encryption process.

19 shows a sample network architecture that could be used for a DRM system. DRM packager (media formatter). Media communication systems are usually composed of unknown (untrusted) and known (trusted) devices. A DRM system server may include the content server (the content source). content descriptions (metadata). A DRM client typically includes a DRM controller. assign and find rights associated with that media and ensure requests for media come from authorized users. DRM systems are typically setup as client server systems where the system receives requests and provides services to clients. When the user requests access to content. A trusted device is a product or service that is previously known or suspected to only communicate information that will not alter or damage equipment of stored data. When the encrypted file is received in the client. A key server assigns and transfers keys that are used to encode and decode media and control messages. security interface (key manager) and a media decoder. DRM systems must identify and describe media.
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. The DRM packager uses the encryption code to process the content and its associated descriptive (metadata) content. Untrusted devices are hardware components or software applications that are unknown or not validated with a provider of data or information.Chapter 9
ciated with digital media. the security interface may be used to gather the necessary keys and parameters necessary to decode the encrypted information. This diagram shows a client that is requesting content and that a server processes these requests. the DRM server first validates the identity (authenticates) of the user by using shared secret information that the client should possess. The DRM system then reviews the authorization of the user for this content and assigns rights for this use of content. The license server may initiate an encryption code that is used to process the media. and a DRM controller (DRM message coordinator). Trusted devices are usually allowed privilege levels that could allow data manipulation and or deletion. license server (rights management). An untrusted device may require authentication based on some type of user interaction before access is granted. Figure 9.

Metadata or meta-tags are commonly associated in media files or programs to describe the attributes of the media content. The content servers’ many functions are to process requests for media content setup a connection to the requesting device and to manage media transfer during the communication session.
Metadata
Metadata is information (data) that describes the attributes of other data.IPTV Basics
Figure 9. These attributes typically
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. DRM Architecture
Content Server
A content server is a computer system that provides content or media to devices that are connected to a communication system (such as through a television system).19. Content servers are typically protected from direct connection to access devices by firewalls or media packing devices.

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.
License Server
A license server is a computer system that maintains a list of license holders and their associated permissions to access licensed content.g. product information (e.
Key Server
A key server is a computer that can create.Chapter 9
include the title of the media. The license server may download a key or other information to client devices that enables a license holder to access the information they have requested. algorithm.
DRM Packager
A DRM packager is a program or system that is used to combine content (digital audio and/or video). Licensing rules may be entered into a digital rights management (DRM) system to allow for the automatic provisioning (enabling) of services and transfers of content. manage. Licensing rules are the processes and/or restrictions that are to be followed as part of a licensing agreement. Metadata) and security codes to a media format or file that is sent from a content provider to a user or viewer of the content. actors or related programs. and assign key values for an encryption system. media format details (media length and encoding formats) and may include additional descriptive information such as media category. A key is a word. The main function of a license server is to confirm or provide the necessary codes or information elements to users or systems with the ability to provide access to licensed content. or program that used to encrypt and decrypt a message that is created in a way that does not allow a person or system to discover the process used to create the keys. License servers use licensing rules to determine the users or devices that have authorization to access data or media.

performs authentication (if requested) and retrieves the necessary encryption keys that allows for the decoding of digital media (if the media is encoded). DRM controllers receive requests to access digital content.
DRM Client
A digital rights management client is an assembly.
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. obtain the necessary information elements (e. Media transfer may be in the form of file downloading.g. media streaming or through the use of stored media. An example of a DRM client is a software program (module) that is installed (loaded) into a converter box (e. hardware device or software program that is configured to request DRM services from a network.g.
DRM Controller
A DRM controller is the coordinator of software and/or hardware that allows users to access content through a digital rights management system. DRM clients may communicate with a module (such as a smart card) or external device to manage keys and decryption programs. user ID and key codes). set top box) that can request and validate information between the system and the device in which the software is installed.
Media Transfer
Media transfer is the process of moving media from the content owner or content distributor to the end user or through other distribution systems. Key renewability is the ability of an encryption system to issue new keys that can be used in the encoding or decoding of information.IPTV Basics
DRM systems may have the capability to transfer and update keys (key renewability).

this allows uninterrupted viewing and navigation (e.Chapter 9
File Downloading
File downloading is the transfer of a program or of data from a computer storage device (such as a web Internet server) server to another data storage or processing device (such as a personal computer).g. File download commonly refers to retrieving files from a remote server to another device or computer. Figure 9. play.20 shows how file downloading can be used to download movies through the Internet before they are viewed. File downloading is primarily used for non-real time applications such as when a program or application is completely downloaded before it is played or used.
Figure 9. rewind or fast forward). stop.20. This diagram shows how the media server transfers the entire media file to the media player before viewing begins. Because the media file has been completely downloaded before playing. Movie Downloading Operation
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.

a server system will deliver a stream of media (such as audio and or video) to the requesting client device (such as a personal computer). real time control protocol (QoS information) and real time streaming protocol (media server flow control)
Stored Media Distribution
Stored media distribution is the transfer of information (media) on a device or material that can be used to store and retrieve the media. optical disks (CDROM or DVD).
Media Distribution
Media distribution is the process of transferring information between a content providers and content users.IPTV Basics
Media Streaming
Media streaming is a real-time system for delivering digital media through a data network (such as an IP data network). or stored flash memory modules.
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. When a user records media from broadcast systems (such as recording a television program). the recording devices typically encodes (encrypts) the media so additional copies cannot be made from the recorded media. magnetic disks. A majority of recording devices are designed to look for copyright control information (CCI) that is contained within the media programs. Examples of media streaming protocols include real time protocol (timing information). The types of media distribution include direct distribution. multilevel (superdistribution) and peer to peer distribution. Upon requesting a program. Stored media includes magnetic tapes. Stored media may be in the form of read only media or recordable media. The client will receive the data stream and (after a short buffering delay) decode the audio and play it to a user. Media streaming uses protocols to control the flow of information and the devices that provide (stream) the media.

services or products between users or devices that operate on the same hierarchical level (usage types that have similar characteristics).Chapter 9
Direct Distribution
Direct distribution is the process of transferring information between the content owner or controller and end users without the user of intermediary distributors. An example of direct distribution is the use of a fixed-satellite service to relay programs from one or more points of origin directly to terrestrial broadcast stations without any intermediate distribution steps.
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. An example of superdistribution is the providing of a music file to radio stations and the retransmission of the music on radio channels.
Media Portability
Portable media is information content (e. storage. Superdistribution typically involves transferring content or objects multiple times. delivery/transfer and use of unique information (keys) by recipients or holders of information (data or media) to allow the information to be converted (modified) into a usable form.
Superdistribution
Superdistribution is a distribution process that occurs over multiple levels. digital audio) that can be transferred to one or more media players.
Peer to Peer Distribution
Peer to peer distribution is the process of directly transferring information.
Key Management
Key management is the creation.g.

Smart cards can be used to identify and validate the user or a service. An example of an industry standard key exchange protocol is Internet key exchange (IKE). electrical pads on the card connect it to transfer Information between the electronic device and the card. DRM systems can have multiple types of keys with different levels (hierarchy) of security.
Smart Card
A smart card is a portable credit card size device that can store and process information that is unique to the owner or manager of the smart card.IPTV Basics
Key assignment is the process of creating and storing a key so a user or device is able to decode content. Examples of keys with different levels include session keys that do not change during a communication session and content keys that repeatedly change every few seconds to ensure that media will stop playing if the authorization to view has ended. television set top boxes or bank card machines. Upper layer keys may be used to encrypt lower level keys for distribution. Key protocols may be proprietary or they may be standardized. Smart cards are used with devices such as mobile phones. Key assignment may be performed by sending a command from a system to a device or it may be performed by providing information to a user for direct entry into a device or system that creates a new unique key. When the card is inserted into a smart card socket. Key exchange protocols are used to coordinate and securely transfer keys in a communication system. A key hierarchy is a structure of key levels that assigns higher priority or security level to keys at higher levels. IKE is defined in request for comments 2409 (RFC 2409).
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. Key revocation may be performed by sending a command from a system to a device. Key revocation is the process of deleting or modifying a key so a user or device is no longer able to decode content. They can also be used as storage devices to hold media such as messages and pictures.

particularly TV programs on videotape. (2-programming) The duplication and sale of program materials. A virtual smart card associates secret information on a users device (such as a TV set top box) that can store and process information from another device (a host) to provide access control and decrypt/encrypt information that is sent to and/or from the device. hijacking and bit torrents. Piracy (1-transmission) The operation of unauthorized commercial stations. and national broadcasting laws. format and store streaming media.
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. Ripping media may occur through the use of a stream recorder. spoofing.21 shows how users may rip media from its original packaging to alter its form and potentially change or eliminate rights management attributes. virtual smart cards may be created. hacking. This example shows that an audio CD is inserted into a personal computer that has had ripping software installed.
Ripping
Ripping media is the process of extracting (ripping it from its source) or storing media as it is streamed. usually in international waters near target regions. Pirates violate flu frequency regulations. The ripping software instructs the microprocessor in the computer to make a copy of the data that is being played to the sound card (audio chip) in the computer and to store this data on the storage disk in the computer. A virtual smart card is a software program. in violation of copyright laws. Figure 9. copyright laws.Chapter 9
Virtual Card
To overcome the requirement of providing a physical smart card to a user. (3-signals) The unauthorized use of cable TV or satellite signals. Stream recorders are devices and/or software that is used to capture.
Digital Rights Management Threats
Some of the potential threats to digital rights management systems include file ripping.

The term hacking has also been used by programmers to solve their programming problems. or to obtain a profitable gain (theft).21.
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. They would continually change or hack the program until it operated the way that they desire it to operate. Hackers may perform their actions for enjoyment (satisfaction). malicious reasons (revenge).IPTV Basics
Figure 9. A hacker is someone or a machine that attempts to gain access into networks and/or computing devices. Ripping Media
Hacking
Hacking is the process that is used when attempt to gain unauthorized access into networks and/or computing devices. Hackers perform hacking.

a sniffer may be able to be setup to look for the first part of any remote login session that includes the user name. they are often associated with the capturing and displaying of information to unauthorized recipients. password.
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.22 shows how hijacking may be used to obtain access to an authorized media session to gain access to protected media. While sniffers may be used for the analysis of communication systems. Figure 9. After the media begins streaming to the validated user. A sniffer is a device or program that receives and analyzes communication activity so that it can display the information to a person or communication system. Hijacking occurs when an unauthorized user detects (sniffs) and obtains information about a communication system. and host name of a person logging in to another machine.
Hijacking
Hijacking is a process of gaining security access by the capture of a communication link in mid-session after the session has already been unauthorized.Chapter 9
Spoofing
Spoofing is the use of another person’s name or address to hide their true identity. Once this information is captured and viewed by the unauthorized recipient (an intruder or hacker). For example. the hijacker modifies a routing table distribution system to redirect the media streaming session to a different computer. This example shows that an unauthorized user has obtained information about a media session request between a media provider (such as an online music store) and a user (music listener). he or she can log on to that system at will. Spoofing may involve registering using one name or identify and obtaining access to the media through the use of other names.

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. Because the receiver of the information has a high-speed download connection. To speed up the transfer speed for the file transfer. This allows the receiver of the information to transfer the entire file much faster.22. Figure 9.IPTV Basics
Figure 9. Each of the computers is connected to the Internet via highspeed connections that have high-speed download capability and mediumspeed upload capability. the receiver of information can request sections of the media file to be downloaded. This example shows that 4 computers contain a large information file (such as a movie DVD). Hijacking Operation
Bit Torrent
A bit torrent is a rapid file transfer that occurs when multiple providers of information can combine their data transfer into a single stream (a torrent) of file information to the receiving computer. the limited uplink data rates of the section suppliers are combined.23 shows how to transfer files using the torrent process.

distribute or manage the program materials.Chapter 9
Figure 9. Torrent Operation
Camming
Camming is the use of a video-recording device to capture audiovisual content from a display (e.
Insider Piracy
Insider piracy is the duplication and sale of program materials. using a camcorder to record a move).g. videotape or other digital media format in violation of copyright laws which is performed or assisted by people who are employees. particularly TV programs on DVD. contractors or supporting personnel of companies that produce.23. An example of
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Analog Hole
The analog hole is the ability for users to copy media in its analog form after it has been converted from digital format to an analog signal.

Digital Hole
The digital hole is the ability for users to redirect media that is in its digital form after it has been received and decoded and reformatted to a display device (such as a HDMI interface). Industry standard defines protocols. digital rights standards can be used defines how the rights of intellectual property will be transferred and enforced as media is transferred from the content owner to the user.
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. Rights are defined in a rights expression language (REL) and rights languages can use data dictionaries to ensure that the commands or processes are defined in a common way.IPTV Basics
the analog hole is the recording of an audio disk by using a microphone.
Misrouting
Misrouting is the redirection of transmission paths or routes. These rights and the rules associated with them are expressed using different protocols. which is placed next to the speakers of a digital stereo system. procedures or tests that are part of an industry standard document or series of documents that is recognized by people or companies as having validity or acceptance in a particular industry. An example of the digital hole is the redirecting of a digital display and processing it into a recorded format.
Protocols and Industry Standards
Industry standards are operational descriptions. file formats and other information that allows systems and products to interact reliably with each other. Industry standards are commonly created through the participation of multiple companies that are part of a professional association. government agency or private group. For digital rights management in IPTV systems. Misrouting may be accidental (error in a router table update) or it may be intentional through the altering or changing of the routing tables.

Digital rights management industry standards include extensible rights management language (XrML). A rights data dictionary is a set of terms that are used by a rights expression language (REL).org. Because XrML is based on extensible markup language (XML).Chapter 9
Rights expression language (REL) are the processes and procedures that are used to define the rights to content. contracts expression language (CEL). MPEG-7. extensible media commerce language (XMCL). and other associated information necessary to enable e-commerce transactions in content rights. XrML files can be customized for specific applications such as to describe books (ONIX) or web based media (RDF). and resource description framework (RDF)
Extensible Rights Management Language (XrML)
Extensible rights management language is a XML that is used to define rights elements of digital media and services. The XrML language provides a universal language and process for defining and controlling the rights associated with many types of content and services. types of users qualified to obtain those rights. Content Guard initially developed extensible Rights Markup Language. XrML started as digital property rights language (DPRL). open digital rights language (ODRL). It was invented by Mark Stefik of Xerox’s Palo Alto research center in the mid 1990s and has transformed into extensible rights markup language (XrML). Using a standard RDD helps to ensure a rights management system will perform processes with an expected outcome (less misinterpretations).XrML. fees or other consideration required to secure those rights. MPEG-21. For more information on XrML see www.0) was based on XML to allow the flexibility of describing new forms of data and processes. secure digital music initiative (SDMI). Several companies including Microsoft have endorsed its use. The initial version of DPRL was LISP based and 2nd version (2.
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.

net.ODRL.
MPEG-7
The MPEG-7 multimedia content description interface is a multimedia standard that adds descriptive content to media objects. Open digital rights language was initially designed by Renato Iannella of IPR Systems Ltd. The MPEG-21 system is based on XrML.
Open Digital Rights Language (ODRL)
Open digital rights language is an XML industry specification that is used to manage digital assets and define the rights associated with those digital assets. The ODRL is a relatively simple language that has been optimized for the independent definition of rights associated with many types of content and services.
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. For more information on ODRL visit www.
MPEG-21
MPEG-21 is a multimedia specification that adds rights management capability to MPEG systems.IPTV Basics
Extensible Media Commerce Language (XMCL)
Extensible media commerce language is a software standard that is used to define exchangeable elements multimedia content and digital rights associated with the media so the media can be exchanged (interchanged) with networks or business systems. of Australia and its use has been endorsed by several companies including Nokia.

The RDF language is well suited for describing resources that are stored on the web such as title. Because CEL expressions are text based. recording companies. playing and distributing of digital media while allowing users convenient access to media content through new emerging distribution systems (such as the Internet). and Internet service provider industries.SDMI.
Resource Description Framework (RDF)
Resource description framework is a general-purpose descriptive language that is used to describe and manage content on the web. author and date. Digital music access technology is a trademark for the technology used for the content protection process developed by the secure digital music initiative (SDMI). consumer electronics. The focus (charter) of SDMA is to develop open industry specifications that protect the rights of media content owners and publishers for storing. The initial development for SDMI (phase I) was to create a digital watermark system.org.Chapter 9
Contracts Expression Language (CEL)
Contracts expression language is a set of commands and procedures that are used to express the terms of contractual agreements in a text based extensible markup language (XML) format. Members of SDMA come from information technology. RDF is managed by the
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. they are understandable and usable by both humans and machines. For additional information on SDMI.
Secure Digital Music Initiative (SDMI)
Secure digital music initiative (SDMI) is a digital rights management standards development project that is intended to control the distribution and ensure authorized use for digital music. visit www. security.

serial copy management system (SCMS). Content protection involves uniquely identifying content. Analog copy protection system may restrict or distort the video signal when media is copied on unauthorized devices. The copy protection system may be used to control the output or media quality on specific outputs. Copy protection system can be designed for analog or digital media. Digital copy protection systems can use authentication and encryption processes to ensure media is not copied or used in an unauthorized way. is a group of companies in the wireless market whose goal is to provide a common markup language for wireless devices and other small devices with limited memory.
The World Wide Web consortium (W3C). secure video processing (SVP).com. For more information about W3C and what they are endorsing as a web based DRM system can be found at www. These protected outputs are interface points in a device or system that are not directly accessible or usable to make copies of media.IPTV Basics
World Wide Web consortium (W3C). scrambling and encrypting the digital assets prior to play-out or storage (both in the network or end user devices) as well as the delivery of the accompanying rights to allow legal users to access the content. There are many types of copy protection systems including copy control information (CCI).
Copy Protection Systems
Content Protection is the process or system that is used to prevent content from being pirated or tampered with in devices or within a communication network (such as in a television system). content scrambling system (CSS). digital trans-
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. formed in 1994. assigning the usage rights. copy generation management system (CGMS). content protection for prerecorded media (CPPM).W3C. broadcast flag. content protection for recordable media (CPRM).

only one time or never.
Copy Control Information (CCI)
Copy control information is the use of data that is provided within or in addition to media that is used to enable or disable the ability of devices to make copies of media. The broadcast flag defines if digital copying is allowed and if additional copies can be made (serialized copying). The CGMS for analog output (CGMS-A) embeds (includes) in the media CCI in the vertical blanking interval of the video signal (lines 20 or 21).
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. high bandwidth digital content protection (HDCP). The copy control bits indicate if the media is authorized to be copied and unlimited amount of times. CCI may be embedded into the content so it can be read and used by devices that may be used to copy content (such as a DVD player/recorder). DVD burners) to determine if the media is allowed to be copied and if so.
Copy Generation Management System (CGMS)
Copy generation management system is a copy control system that embeds (includes) in the media copy control information (CCI) that is can be used by replication devices (e. high definition multimedia interface (HDMI) and extended conditional access (XCA). in what format types. The CGMS system may be used for analog or digital outputs. The CGMS for digital output (CGMS-D) embeds (includes) in the media CCI in the digital video protocols such as digital transmission copy protection (DTCP or high definition multimedia interface (HDMI). The CCI system uses two bits to define the copyrights associated with media.g.
Broadcast Flag
A broadcast flag is a data word that is sent in a broadcast channel (such as a digital television channel) that indicates who can use the content.Chapter 9
mission content protection (DTCP).

SCMS has been used in digital audiotape (DAT) recorders and in mini-disc recorders.
Content Protection for Recordable Media (CPRM)
Content protection for recordable media is a copy protection system that is used to control copies of recordable media (such as blank DVDs). in the disk) to determine if initial copies or second-generation copies are permitted. To decode and play the information.g.g. via DVD burners). a player with a decoding algorithm must be used.
Content Protection for Prerecorded Media (CPPM)
Content protection for prerecorded media is a copy protection system that is used to control copies of stored media (such as DVDs).
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.IPTV Basics
Serial Copy Management System (SCMS)
Serial copy management system is a copy control system that uses information contained in the media (e.g.
Content Scrambling System (CSS)
A content scrambling system is a method of encryption that is used for stored media (e. DVDs) to prevent the use or copying of the media information. The CSS process is designed to prevent access to the media from devices that do not have the appropriate decoding algorithm so the media cannot be copied or manipulated by unauthorized users and devices (e. copied once or copied all (unlimited). SCMS uses permission flags that indicate if the media is allowed to be copied never.

encryption and authorization of services. full and restricted.Chapter 9
Secure Video Processing (SVP)
Secure video processing is a method of ensuring the rights of video content are enforced through the use of hardware. a display or a recorder). Sony. Devices that use DTCP exchange authentication certificates and keys to setup a secure communication session. Matsushita and Toshiba for the IEEE 1394 (Firewire) system. DTCP has 2 levels of security.
High Bandwidth Digital Content Protection (HDCP)
High bandwidth digital content protection is the commands and processes that are used by the digital video interface (DVI) system to perform authentication. software and rights management systems.
High Definition Multimedia Interface (HDMI)
High definition multimedia interface is a specification for the transmission and control of uncompressed digital data and video for computers and highspeed data transmission systems. HDMI is a combination of a digital video interface (DVI) connection along with the security protocol HDCP. HDMI
363
. The HDCP system allows devices to identify each other and determine what type of device it is (e. Hitachi.
Digital Transmission Content Protection (DTCP)
Digital transmission content protection is a copy control system that was developed by Intel. A secure book loader system is designed to be tamper proof. Full authentication is used when the devices have enough processing power to perform authentication and encryption.g. A secure boot loader is a process that is used when a system is started that ensures operations with a system is secure.

the HDMI interface will reduce the quality (lower resolution) of the digital video signal. It has the capability to use and renew security on smart cards.
Extended Conditional Access (XCA)
Extended conditional access is a digital transmission content protection is a copy control system that was developed by Zenith and Thomson for one-way and two-way digital interfaces.
364
.IPTV Basics
has the ability to determine if security processes are available on the DVI connection and if not.

Standards Groups
IPTV Standards Groups
A standards group is organization or firm that is charted to create or assist in the creation of product or service operational.Appendix 2 .
375
. Motion picture experts group (MPEG) is a working committee that defines and develops industry standards for digital video systems. MPEG is part of International Standards Organization (ISO). These standards specify the data compression and decompression processes and how they are delivered on digital broadcast systems. performance and other types of specifications.
Society of Motion Picture and Television Engineers (SMPTE)
The SMPTE is an organization that assists with the development of standards for the motion picture and television industries.
Motion Picture Experts Group (MPEG)
Motion picture experts group (MPEG) standards are digital video encoding processes that coordinate the transmission of multiple forms of media (multimedia). Standards groups usually represent the interests of a group of companies that want to create products or services that are interoperable with each other.

Advanced Television Systems Committee (ATSC)
The Advanced Television Systems Committee (ATSC) is an international non-profit organization that assists with the development of advanced television technologies and systems. in coordinating like activities. and satellite. ATSC was founded in 1982.
Association for Radio Industries and Business (ARIB)
Association for Radio Industries and Business (ARIB) is an association in Japan that oversees the creation of telecommunications standards. The membership of the ATSC represents a wide range of broadcast and consumer electronics segments including broadcasting.ETSI. satellite systems. and satellite broadcasting. high definition television (HDTV). cable television systems and mobile communications. computers. consumer electronics. They work with other international standards bodies.org.
Digital Video Broadcast (DVB)
Digital video broadcasting is the sending of television signals over digital transmission channels. These standards can be obtained at www. motion pictures. data broadcasting. surround sound audio. DVB industry standards that are published by the joint technical committee (JTC) of the European Telecommunications Standards Institute (ETSI). standard definition television (SDTV). including the International Standards Organization (ISO).
376
.IPTV Basics
European Telecommunications Standards Institute (ETSI)
An organization that assists with the standards-making process in Europe. ATSC industry standard include digital television (DTV). DVB transmission can be over different types of systems including broadcast radio.

UPnP includes the automatic recognition of device type. setup. is a group of companies in the wireless market whose goal is to provide a common markup language for wireless devices and other small devices with limited memory.Appendix 2 .Standards Groups
Cable Laboratories.
Advanced Television Enhancement Forum (ATVEF)
Advanced Television Enhancement Forum (ATVEF) is a group of companies and industry expert that come from multiple industries (cross-industry) that work towards the creation of industry standards for combining Internet content and broadcast television. operation removal of consumer electronic devices. Inc. communication capability.
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. service capabilities.UPnP.
World Wide Web Consortium (W3C)
The world wide web consortium (W3C). formed in 1994.org. More information about UPnP can be found at www.
Internet Media Streaming Alliance (ISMA)
Internet media streaming alliance is an association that works to help develop and promote standards that enable streaming media applications.
Universal Plug and Play (UPnP)
Universal plug and play is an industry standard that simplifies the installation. activation and deactivation of software drivers and system management functions. (CableLabs)
Cablelabs® is a non profit consortium of members from the cable television industry founded in 1988 that oversees and assists in the development of technologies used in cable television systems.

More information about DLNA can be found at www.IPTV Basics
Digital Living Network Alliance (DLNA)
Digital living network alliance is a group of companies that work to create a set of interoperability guidelines for digital media devices that operate in the home.DLNA.
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.org.